I will soon have a home and figured now's the time to do a proper home server, especially since it's going to come with cat 6 run from the main panel to just about every room. I code for a living, but at the same time network is a massive gap in my knowledge, as are servers, and I was hoping to use this as a learning moment as well as just a way to optimize things. I've been doing research for a few weeks now on and off and feel like I've got more questions than I started with, so I'll just vomit them out and if anyone has some guidance I'd really appreciate it.

Some information:

1. I'm willing/able to spend to get quality/simplicity. Time is the much bigger crunch for me right now, and I'd much rather buy something that works even if it costs more than cobbling together some deals.

2. Related to 1, I'd like this to not become my fulltime second job/hobby. I will at some point try to expand to a full home lab, and do want to use this to learn about things I feel I should understand better for general knowledge and my career, but i'd love for core functionality to mostly "just work" after configuring so when I don't have time to do that I'm not stuck telling everyone "oh yeah it'll be broken until I find time to fix it".

Things I know I want-

1. Some sort of NAS. From my research Synology comes up a lot as the "it's expensive but it'll just work" option, and I probably want something like a 4 bay of NAS specific several TB HDD's in something like raid 5/6/10. Pricey as hell but I'm most willing to spend on this as the cost might very well be split by the family members who want me to guinea pig all this.

2. I will have a camera system and would prefer to not have it sending data outside my network. This is the area i've looked at the least, as it's a little farther down the road, but I know others who have things like Arlo and lets just say i'm not super impressed. Obviously this brings up question like remote access to said camera's and where I'm storing the data (nas? Somewhere else?)

3. I'd like to mess with a media server. Plex/Jellyfin constantly come up in my research, so I'll be looking into those, but I've also got a bunch of audiobooks that I'd love to be able to easily share, and I think there's software for that stuff as well.

4. Pihole strikes me as the other "well if you're going to do this, you might as well" option that i'm aware of. Realllly need to better understand networking in general, but I hear these days it can kinda be installed and quickly configured and then left to do its job.

5. Related to all of this, Casa OS keeps coming up as a very good tool for a beginner like me, since it streamlines the handling of docker containers and also file sharing. However it's not really an OS, since it must actually run on Debian (i think?) for now (zima OS still in testing?).

Stuff I'd like to mess with but doesn't have to happen right away.

1. Eventually the aforementioned NAS would be backed up offsite to another NAS at another family members house, once I know what the hell I'm doing.

2. Proxmox constantly comes up as THE tool to use, but it leaves a lot of questions for me. Obviously if I start trying to do lab environments and screw with VM's it's going to be great, but my understanding is that I probably don't, as a beginner, want to say load up a device with proxmox and then have it host debian which installs CasaOS as it'll get a little more tricky to have everything talk right? Unsure on this part.

3. Anything else I'm forgetting. One issue I keep having with this is a LOT of the information out there is either too complex for me to really grok or just says "well yeah you could do ANYTHING with this" and it just sorta assumes I know what the options are. If there's anything else worth checking out I'd love to know.

Hardware I've come across-

1. Synology - Already mentioned but seems like they're a common go to for a "more money than skill/time" situation like mine.

2. Zimaboard - My understanding is it's underpowered for its price, but the main draws are that it's VERY low power, small, and quiet. What it could actually do from my list above is where i'm unsure. I see people are supposedly using it for Plex servers and what not, and I'm pretty sure it's not going to make any kick ass lab environments, but being quiet, small, and maybe a bit closer to plug and play seems tempting (I know they make the blade and a few other products but it all seems greek to me).

3. Various mini computers - I've got a minisforum machine from several years ago that I currently use as a living room computer for light gaming and mostly playing movies and the like. Not sure if i could just wipe it and convert it to be the starting point (more on that later). I know used 1 liter mini pc's from companies like HP are also popular.

4. The MS-01 - Similar pile as the last one but my understanding is this is the kind of thing that's probably really cool if you actually know what the hell you're doing. I'm 99% positive it is vast overkill for my purposes, but I'd like to eventually get to the point where I could understand why I might want something like this. My understanding is if I knew what I was doing I could probably drop proxmox on this and do everything I could ever want and more, but I feel quite far from that.

Some general questions I have -

1. The thing that kicked this all off is my new place likely having fiber, and cat 6 drops throughout the building. Architecture is something I'm still a little shaky on. I assume i'm going to need my own modem/router (just because the cox routers are meh and not really configurable from last I checked), and then that routes to the server first???...or something(seems like a must if you want the pihole to do anything)? I've seen lots of niffty network diagrams at this point but they're all from people WAAAAAAAAY beyond my skill level doing much more ambitious stuff, so it gets hard to understand. If anyone has a simple home network diagram/guide to look at I'd really appreciate it.

2. I'm just in general going to need to learn more about networking, especially in a home environment. Should I eventually get those camera's set up, I want to understand how to let them talk to internal storage and what not ,but not get out to the web...or..something (again remote access seems nice, but also like a massive security concern). I know speed is also a big factor i'm going to need to better understand. Having a fiber connection in only to be bottle necked by a crappy router or a 1gigabit port is just a waste of money, so that's something else I'd like to better understand.

3. I'm a little unclear on how to deliver the media in a media server to the various screens throughout the building. I've got cat 6 to all of them, but I suspect i'm still going to need, at the very least, a cheap computer to hook up to it and then display the image to the monitor/TV? This is why I assume I can't just wipe my current mini PC and reuse it as a server, because I still need it to receive the data from the home server (or at least a web browser?). A part of me feels like if I got a powerful enough server it should be able to server the media direction to the screen, but then you'd need some sort of HDMI/DP drops as well from the server to all your screens?...or something?

Sorry for all the rambling but I've got an odd mix of knowledge and ignorance so it's been a little difficult to research when half the video is stuff I already get, and the other half blows past me or just assumes I know about the parts i'm trying desperately to learn about.

I'm setting up a server with nextcloud, plex, matrix and some other things I don't yet know, for some friends and family, (about 20 people if I get lucky)
and now I heard of a thing called single sign on/unified login. (Login to different services with the same user/pw and/or login once, access to all services)

so far I found out about Keycloak https://en.wikipedia.org/wiki/Keycloak

is this what I'm looking for? does anybody have experience in this? Are there other/better/simpler solutions for this?