If you are struggling to find your purpose, I have good news for you.
Look for your bad habits, your perceived limitations, unfinished tasks and make them your purpose to sort out. Write them down, draw out an action plan and monitor progress. If you cannot make any progress after 60 days and see yourself falling back to the bad habits, then you are not ready. Start again and be persistent until you notice tangible progress.
Greater purpose will be revealed to as you remove the stumbling blocks in your life.