The official Gundam YouTube channel has made a lot of stuff available to watch for free, legally. One of them is the prequel series telling the origin story of Char Aznable: Mobile Suit Gundam: The Origin. This is some top-notch stuff, and I'll embed the English playlist below so you can watch at your leisure. There are English Subtitled and Dubbed uploads if you prefer, and Part IV is forthcoming which should wrap this up.
I make no bone that I prefer the original Universal Century continuity over all the alternatives, no matter how good or bad they are, and a lot of that comes from Char. Like many fans, Char was my sympathetic character to follow--not Amuro Rey (the whiny shit)--in the original series and I still liked him in the sequels that followed. Having an entire series of short films dedicated to his origin? Hell yes, I'm all about that- and in such glorious animation to boot. Please take the time to watch, as you prefer your anime to be enjoyed.