Shaving... Help a teen out. (Lol)

The first time I shaved (with a disposable razor) I didn't cut myself. But a few weeks ago we had a school trip thing to the beach and my parents didn't let me shave, so I used some of my mother's razor blades that she never uses. But that only worked once out of luck and believe me, NEVER SHAVE WITH JUST A RAZOR BLADE.

I got a nick but obviously I know that an open wound is dangerous and can cause infections. I never shaved that way again.

But now, I really want to shave in a safe way and don't know how. I don't want to buy one myself and lie to them either.