new to this

[Neuromancer815]

hello, im trying to get into repacking games for the first time ever, for my own private use. i have a very slow wifi where i live and its always a pain to download anything larger than a few gigs. so what i wanna do is compress the games im currently not playing for later use. ive been directed to this forum as a great resource to help me get started, and ive been looking through the sticky for a few days now and id be lying if i said it wasnt very overwhelming, especially since i know absolutely nothing about compression and repacking. i am willing to put the time and effort to learn but im really not sure where to even start? id very grateful if i could get some guidance as to where i need to start this process. currently all i have done besides reading the stickies is downloaded this <http://freearc.org/download/0.666/FreeArc-0.666-win32.exe> and this <https://jrsoftware.org/isdl.php#stable>. i have tried compressing a game, sniper elite 4 to be exact, since i dont have any smaller games to test on but after seeing how much time it was gonna take i aborted it for the sole reason of not being able to use my pc for that duration and not knowing whether or not it was gonna work