Even as simple thing as putting a program in start-up is hassle and varies depending upon distribution, and I went on rabbit hole just like you said.

If you want to start program on login(like on windows), then you need to use you DE’s settngs GUI. If you want to start program on boot, then you need to enable startup script in your init.

So problems like in Windows are solved like in Windows.

and their grandparents are using mint.

My grandparents(and parents. and me.) are using Gentoo, but I recommend to people OpenSUSE Tumbleweed.