I heard someone say once that one of the best things that helped them develop a growth mindset was lifting weights. Consistently doing 3x5 heavy squats, deadlifts, and presses just three days per week will make a visible change in most people's body remarkably quickly. And seeing that change in yourself really helps reinforce that you can change your situation.
I thought that was an interesting observation but I'd like to suggest expanding it to physical activity in general rather than specifically powerlifting. There are many different activities (for example HIIT, martial arts, gymnastics, rock climbing just to name a few) that will make a significant physical change in your body. When you stick to one of those activities and document your progress with data, photos, etc there's something about seeing that change happen to the blob of matter that is "you" that really expands what you consider achievable for yourself.
I thought that was an interesting observation but I'd like to suggest expanding it to physical activity in general rather than specifically powerlifting. There are many different activities (for example HIIT, martial arts, gymnastics, rock climbing just to name a few) that will make a significant physical change in your body. When you stick to one of those activities and document your progress with data, photos, etc there's something about seeing that change happen to the blob of matter that is "you" that really expands what you consider achievable for yourself.