I had an endoscopy done a few months ago and they found nothing but mild reflux all biopsy came back clear. Still taking omperzole and such for the reflux. I’m 22 years old and very healthy. Could my reflux turn into cancer of the esophagus?

Not in short term. Cancer of the esophagus is a possible long tern consequence of reflux/Barrett's esophagitis. The fact that you have mild reflux, like a majority of adults, means there is no sign it will happen in the near term. If it worsens & you have it for decades it is might be something in your future. At this point I wouldn't lose sleep over it.