martymusic has a good channel for that too. I've been playing for a few years now and that's where I started. legitimate music classes can help I'm sure but that's pricy and it's certainly not impossible to play self taught. (source: am self taught. probably not as good as i could be because of it, but i have bigger issues than guitar lessons rn lol)

and me...

if it's mostly muting it's probably just something that'll go away with practice as you gain strength/get more used to the positioning. the size of the guitar will affect it some (i play a half size because I'm just generally a small person lol) but even then once you're used to it it won't be that much of a difference. maybe look up some exercises for it if you want to speed things up rather than just playing until it works.