For prenatal visits you would visit an Obstetrician.
An obstetrician is a doctor who specializes in pregnancy, childbirth, and a woman's reproductive system. They practice obstetrics: the branch of medicine and surgery concerned with childbirth and the care of women giving birth.
Gynaecology / gynecology is the medical practice dealing with the health of the female reproductive systems and the breasts.
Outside medicine, the term means "the science of women". Its counterpart is andrology, which deals with medical issues specific to the male reproductive system.
Obgyn: A commonly used abbreviation. OB is short for obstetrics or for an obstetrician, a physician who delivers babies. GYN is short for gynecology or for a gynecologist, a physician who specializes in treating diseases of the female reproductive organs.
Pregnant people go visit an obstetrician or Obgyn for healthcare needs specific to their pregnancy. You can pick one on your own, or you could ask your regular primary care doctor if they have any recommendations. Honestly I'd probably ask friends & family first.