I want to sleep with my half brother
Why do you want to sleep with him?
I would feel ecstatic and excited to do it.
Its not a great idea to want to have relations to someone you are related to. While you may find that you are attracted to them, it is very dangerous to down this path.
Shut up you are no one to tell me what to do.
What you are talking about doing is incest and it is very wrong. How about you consider finding an appropriate boyfriend for yourself?