Remote Access that's safe and not a scary nightmare

My child (who does not live with me) has a PC. He's pretty good at sorting problems out for himself, but he sometimes needs extra help. We've tried doing this over phone and video calls, and it's an unfun experience for both of us.

Is there a remote access software that would fit our needs? I want to be able to connect to his computer over the Internet and have some level of control when he's logged into his account. I'd need to be able to open files, I wouldn't have to be able to save them. He's using Windows 11. I think he's using the home version. I'm using Windows 10 Pro. We both have reasonably good Internet speed.