Realize that most of the people that you're watching on YouTube probably are not learning guitar in a systematic comprehensive matter like you're doing with GF 1. I'm pretty sure that most of those overnight rock stars simply learned to parrot back a few licks on YouTube and stitched them together to create something flashy. And that's likely all they'll ever be capable of doing. You on the other hand, are laying the early foundations for truly learning the guitar and being able to do so much more than imitate others.
Also, doing the core curriculum tutorials can get very frustrating and even leave beginners (like me) feeling hopeless about ever learning to play. From what I've been able to distill from this forum that's something that happens to just about everyone. One word of advice: Don't get caught up in trying to keep up with the instructors in those 'play along with the music' lessons. They're professional guitar players who are playing those tracks at a rate that's comfortable for them, not you.
Use the rate tabs to the left of the video screen to dial down the video playback rate to a point where you can focus on technique. Right now, it's much more important for you to learn proper technique and avoid developing bad habits. Absolutely do NOT fall into the trap of refusing to move on to subsequent lessons until you've mastered each lesson. That's a death sentence. You can always circle back and work on speed after you've finished the course.
"Whatever you are, be a good one" - Abraham Lincoln