I do not think you would know for sure that you are gay at 12-years-old and neither will your friend. Wait until you are sure before asking questions such as these as it may backfire on you.
you ask him.
You don't ! He probably will not know his sexual identity for sure at this age anyway.
you could just ask him and see what he says. He may not be gay and he may like you the same amount that you like him. You would never know until you ask or try.
ask her out
Get the boy alone and ask him tell your friend your mum wants to know his mums number or something
start being her friend and get to know her then ask her out
Talk to them and ask why they did it.
Ask him. It might seem odd, but do it. Or, have a friend (that is friends with both you and him) ask him.
first get to know her as if she was your sister then ask her if she sees you as her boyfriend
A 13 year is suppose to be your friend. That age is not ripe for dating.
If a 17 year old wants to move in with an 18 year old then the person who is 17 needs to ask their parents to move in with this friend scince the 17 year old is not an official adult
well tell him how you feel about him