What kind of doctor can remove a large nevi (birthmark)?

Depends on situation: Some birthmarks can be removed with simple surgery by a general surgeon.If located on a facial structure or very large i generally send them to a plastic surgeon. Some birthmarks respond to laser treatment & that may be available thru a plastic surgeon or cosmetic dermatologist.

Many: It all depends on size of the lesion, location of the lesion, and experience of the surgeon. A dermatologist or plastic surgeon are both good choices.