At the very beginning of the movie, a naked (full frontal) woman is shown in a campaign pose.
Early in the movie the main character, Linda Lovelace, is talking to an old man. He has a cane with a mirror on it which he positions so he can look up her dress. Her vulva/slit can clearly be seen for a couple of seconds. Full female genitalia is visible briefly.
Some people are shown having sex. Usually, breasts and butts are visible, sometimes pubic hair on the females. Some implied blow jobs.
A woman takes off her clothes and washes herself under a waterfall. She is fully nude, breasts, butt, and pubic hair visible.
A woman is shown in a bathtub, breasts visible.
A woman takes off her dress, revealing her breasts.
A man and woman are shown running in a field, breasts, butts, pubic hair, and the man's penis are visible.