What to do if i'm a teenager and i masturbate once or twice every other day and have started masturbating not too long ago, is this normal?

Yes: You're normal. Almost every one of your friends is doing exactly the same thing. I'm sorry that there are people in this world who are peddling superstition and may have tried to frighten you. It's actually good for you. Think about that one special person in your future, maybe instead of junk you saw online. Maybe you could even talk to your same-sex parent about it. Enjoy growing up.