What can u do to increase my speed and stamina 🙏

Today i did film study in the morning, i watched a breakdown on kirie. Then i went to the court with my friend and we did some shooting drills. My middys went good, but my form felt off (even tough i scored almost always), and my 3s also went really good. I'm noticing improvement on 3s, one of my weakest points, perfect. I also did a 2v2. I need to work on defense 😐. Then i did plyometrics, they went good

i can’t really make my shots confidently, any advice how to deal with pressure defence, shot selection?