disroot is quite decent. I like their (privacy) vibe and the set of semi-independent services they provide.

Yeah that’s a great idea! I use that too. An encrypted USB drive makes sure you can trust the data not leaking, and spaced repetition can (should) be practiced to memoize the password. Then you’re good I’d say.

Technically KeePass can “merge” and has some sort of conflict resolution, but you’re right that forgotten and unaddressed conflicts can lay around for unlimited time without you noticing. It’s the main problem with keepass + syncthing.

It’s a bit sad that you’re downvoted so hard. You obviously have good intentions, just not having a good grasp yet if I may be frank. The solutions in this post are what you should follow IMO. In short, USB thumb/hdd drives with your important data. Encrypt the whole USB if your devices are under Linux if you wish. Use a proper password manager like KeePass to secure it additionally, with a strong master password of course.

Hey, welcome to the concept of self-hosting! This is where I was 15+ years ago.

Realistically, I’d just recommend installing something and trying it out. You’ll iterate many time before you’ll slowly start to align somewhere I suspect, in terms of software/approaches etc.

If you want the very first steps, then why not simply connect your old PC to a monitor and install a Desktop version of Mint? It’s super-“wrong”, but it’ll get you started. Once you reach a stage of not wanting to waste memory/CPU on a graphical system, you’ll be able to do something like systemctl disable lightdm.service and voila, graphics don’t load on start anymore. Once you get even more confident, apt remove gdm3 xfce4 xfdesktop will remove any extra disk space (I’m dropping DE names that I approximately remember off the top of my head). With the packages for graphics gone, your system is indistinguishable from a server now.

Overall it’s a nice path to walk, or at least it was fun and somewhat educative and very frustrating and giving a sense of control for me personally. Do you have any specific questions?