I am 35 years old and single. Isn't it a little late to learn photography as an apprentice? What age do photographers usually reach?

There is no sooner or later to learn photography. When you get older, you will understand some knowledge faster and more efficiently. Photographers, if they like, have a little sense of accomplishment, and if their physical strength is ok, they can continue to grow old indefinitely. Sometimes, the older people get, the more trust they have and the deeper their cultural background.