There is a girl I know likes but I don't what do I do

I may be taking your question the wrong way. But, when I first read it, I thought that it said something about "There is a girl that I know that I like, and I don't know what to do."

That may not be the case though, after I re-thought what you were asking, I then got this out of your question, "There is a girl I know that likes me, but I don't like her. What should I do?"

If it is about a girl that you like and don't know what to do, then I would suggest the following:

Get to know her. Invite her to participate in a game that you are playing. Ask her if she is interested in something that you are. Maybe find out activities that she is in and see if you can get involved in them.

If it is about a girl that likes you and you don't like her, then it would help to know what she is doing that bugs you in order to give a better answer.

I understood the question as "There is a girl I know who likes me, but I don't like her... what do I do?"... but I don't think she has to be doing something that bugs him... maybe there is no chemistry for him... sadly, as most of us have experienced at one time or another, sometimes one person does not reciprocate another person's feelings for him. Returning to the question... I think you should be nice yet straight with her... there is nothing worse than leading a person on.