“how do i forgive myself for something bad and move on with life and my future”

Another soul answered...

I'd say the first step is accountability. Apologize to anyone you may have wronged (if you wronged yourself, apologize to yourself), and work on how to become better in a future, and use this wongdoing as a lesson. If you've done the steps to take accountability, it'll be much easier to forgive yourself. Good luck!