

If you just want something simple that does the job, you can try a turnkey solution like YunoHost. There’s several other ones out there. Some with containers, some with more or less pre-packaged software… If you want to learn more during the process, maybe don’t and do it yourself because these things don’t teach you a lot. There’s some resources like the awesome-selfhosted list in the sidebar of this community. But I think for installing services you’d mainly look at the specific documentation of the specific service you’re just about to tackle. And maybe read up on Docker containers etc to judge whether you want to do it that way.




I think educational activities work best once they have some application to someones life. So it’d be something within the realm of a 7yo. And it’s not fun unless there’s a sense of achievement every now and then, along with all the stuff to learn. So probably not too steep of a learning curve.
Sadly they discontinued Lego Mindstorms. I think robotics is a great hands-on topic. People can grasp what they’re currently doing, why they do it, and what it’s good for. It has a tactile aspect, so you’ll train dexterity as well and gently connect the physical realm with the maths.
But other than that, I bet there’s a lot of things you can try. Design a website (and deploy a small webserver). Maybe some easy to use photo gallery if they have a tablet or camera. Maybe a Wordpress for them to write a Blog? They should be familiar with the concept of a diary. Kids love Minecraft, so maybe a Luanti server if you’re into Free Software. But learn how to add NPCs and animals, that is (or used to be?) a complicated process in Luanti and the world feels boring and empty without. A chat server to their loved ones could motivate them to read and write text (messages). Or skip the selfhosting aspect and do the kids games available for Linux. Paint, LibreOffice…
I like the recommendations from other people as well. Sadly I don’t know which kids programming language works best. I think I heard you can just go straight for Python as well. Not sure if that’s true or what age group that applies to. It’s a bit more involved to learn the syntax and why you need brackets around certain things etc but at least they get to learn the real deal and something properly useful. 7 might be a bit young, though. And there might be a language barrier. But that applies to all the computer stuff behind the scenes, unless you’re a native English speaker.