How can i improve my slouchy posture? i work at a computer for years and now my shoulders slouch. i want to improve this.

Yoga physical therap: Work with therapist for posture correction many will work with you to correct your posture if not caused by a structural spine deformity like schuermanns kyphosis if straightens out lying on a flat surface then it is a postural kyphosis can be improved with therapy.

Yes you can: Posture can improve with training, exercise, strengthening the posterior muscles, and attention to your seating. I suggest a small mirror in your work space to give you a visual on your progress and posture.