Can a genital wart look like a pimple? have one under head of penis on the skit had a white head on it?

No, warts are not at all like pimples. They are not inflamed (red, irritated) or have white heads. However, herpes could appear like this. If the problem continues or you remain concerned, you'll need to be professionally evaluated in person. Good luck.

They can look similar if you're not sure what they look like, but a doctor can generally tell the difference. You should get it checked out by your doctor to be sure. There are also multiple images online so you can look and compare your bumps with those to get a better idea, but I would still recommend having your doctor take a look.