How do I get better at basketball by spring?

I used to be realllly good at basketball in elementary school. I used to be the star, I scored all the points and I blocked all the shots. I used to want people to come to my games and watch. But ever since middle school my confidence went out the window because I got in a fight with the people on my team and they all went against me and hated me( im in 8th grade btw). Now I want to join a bball team in spring and be reallly good. I know the basics of basketball but as I said before my confidence was gone therefore my skills also vanished. But im ready to do it now for real. and once im in high school I want to try out for the team and make it. How can I do this?How should I pratctice?What will help me get better? What are some drills?