Sex but no doctor

In the last year I have become very sexually active with my boyfriend. I have a few friends that were talking to me about their lady doctor/gyno and I didn’t know I needed one when I start doing it because nobody talks about that we’re just told to use protection and be careful and stuff. Am I supposed to have one? My parents don’t know I’m active and I don’t want to tell them.. I’m not too young and when we do it we are very responsible. I’m just wondering what the gyno is for and is it important?