u/Any-Ideal1601

Hey everyone, so my whole life I’ve had bad posture due to an excessive video games and generally not taking proper care of posture. I’ve started work on this and go to the gym. The issues is I feel like my left shoulder (first pic) is forward a lot. When I try to correct it, I feel tension and a little discomfort in the collarbone area. I also feel discomfort in the upper back on that side. I also noticed I can’t flex my lat at all on that side and my chest as well. The second pic is my right shoulder which I have no issues with. Please let me know what I can do or if there is anything problem at all. Thank you.