How do I tell my family I am bisexual

I am only 12 but I have known I am bisexual for a while now. I have not been able to tell my family . My sister recently came out to my dad telling him she was a lesbian and he hasn't made contact with her since then I don't see my dad very much rarely will I and do not want to not see him at all. Also my bestfriend Genesis also my wife ( she calls me her wife ) we kissed today but idk of it ment anything to her . PLEASE HELP ME . WORST PART IS I HAVE  A BF JUST HAVE NOT TALKED TO HIM FOR WHIL HE LIVES IN MEXICO AND WORKS TO SUPPORT HIS FAMILY.