I'm also really scared to tell my family I have already told my brother bc he is always supportive and he didn't really think much of it besides saying cool and going back to whatever he was doing. He said to just straight up tell him and I feel like I'm making such a big freak out of something that could be really easy, so I'm not very helpful, but I also need help.
Too early to tell, better take your time to be certain ( Me ex thought she was bi ,but she reached 23 she was like nope, I don't enjoy girls).
first, dont put your number on the internet, lol you never know who will try to text or call you ( pervs), um I dont think you need to tell them right now, just keep it to yourself for now, I am not saying you arent bi , but it could be just a phase too.
Why must you tell them? That's a very personal subject...