first gyno visit?

hey ladies! im 15 and i read online that youre supposed to go to the gynecologist between 13 and 15, but i havent been yet. my mom thinks you're supposed to go when youre sexually active, can someone clarify when my first visit is supposed to be? how do i ask my mom without being awkward? also, does sexually active mean that you had sex or can it be stuff like fingering?

thanks! :)