What are the best resources to get started with 3D modeling and printing now that the hobby is quite mature?

I've had an interest in 3D printing since first hearing about it many years ago, but at the time printers were expensive and learning materials and resources were scarce. Nowadays, it seems like 3D printing is as common as regular old 2D printing but I feel left in the dust.

What's really making me want to get started now is I've collected a lot of junk over the years that I've told myself I could repair, but a lot of the repairs would be much easier with a 3D printer and custom modeled parts. Dearest to me would be an old watch that my grandfather gave to me before he died. The part of the watch that connects the strap to the case (lugs, I think it's called?) has broken off and gotten lost, and it's a proprietary part with no replacement parts available. I'd love to just 3D-print a solution but have no idea how to get started.

I consider myself a creative person, I have plenty of experience with Photoshop and illustrator, but I have never once dabbled in 3D modeling software like Blender or AutoCAD. The closest I ever got was peering over the shoulder of an artist who was working on a video game character model in Zbrush, or maybe working on custom Half-Life maps in Valve Hammer. So I'm looking for the most basic, easy-to-follow set of instructions to get me from zero knowledge to successfully printing bespoke DIY repair parts at my local makerspace.

Would also love to have this be a discussion on 3D printing in general. How did you get started? How have the tools and techniques evolved over the years? What do you think are the next big things coming in the hobby? What are things you wish you knew when you started but only learned after mistakes were made? Share your thoughts and anecdotes, I'd be happy to read them.