How can I get rid of the crease (double eyelid) and have no crease (single eyelid)? How can I do this with out surgery?

I suggest posting photos for us to give you a better idea if there are alternate options.  Sublative, other radiofrequency treatments or laser treatments may help without the need for surgery.  Best, Dr. Emer.

A photograph would be helpful to even understand what your eyelids look like.  Generally though, it is always possible to raise a crease or fold but seldom possible to lower a fold.  It is certainly improbable that it could be achievable without surgery if it were possible at all.

Difficult to say without a photograph or clinical exam. Without surgery there aren't any great options I'm aware of but a standard blepharoplasty may be what is needed. This can often be done under local anesthesia. See a plastic surgeon near you for more information.