Older User ,shaky Knowledge of advanced Terminal, Devices /Network taken over,Very advanced skills, need answers , so I can helop myself !!

Hello all,
I'm call and this what happend: I was in a bad situation , I had been suffering from alcohol addiction for 30 years and one day a good frind that had stopped came to me and left n RPI 1 on my table and said, if I remember how to hook up a VCR, the I should try this-Long story short, it was in 2015, now I have 5 Rpis a couple of very old PC s and I have been sober as a judge ever since. Sadly my friend and mentor paased awway a couple of years back ! To the issueWhile installing Ubuntu 20 I decided to aske for some answers or ahint where I should turn. I know next to nothing about vitual properties an advanced networking and sourcecode and the Terminal knowledge, that is required.But and nobody outside of the Linux/Terminal world believesme, that it is even possible !!But I and all my devices , what I call my nertwork have been in a huge virtual box, controlled viaremote means! Everytime I try bto install something, itsd will be magicly cancceled or denied! Grant it I probaly made a the beginners mistakes and did all the wrong things and I dont enough, but it wouldnt matter, because these guys are way advanced ( I follow them on dmesg).Anyway I am looking for an answer or at least a hint because, all I want is this to end, to be left alone with my pis and my old pc s !!Anything you could will be very much appriciatted. rgds Call (short for Malcolm )