Best friend and I like the same girl, what now?

At first I thought he maybe liked her so when I started too, I asked him some things to find out if he liked her. I was certain he had no interest in her, so I told him I liked and thought I was safe to flirt with her. However about a week after I started flirting with her, he suddenly shows up more and tries to flirt with her right in front of me. He constantly gets between me and her, not letting me be alone with her. It seems he only liked her after he found out I did. I am almost certain she only sees him as a friend by the things she told me and how she acts with him, even telling me he is just a guy friend to her. He has no clue how to flirt really or tell the difference between fun and flirting. He just pokes her, throws stuff etc basically flirts like he is in grade 8, acting immature. She will do these things back not to flirt but because its fun at times she even does it to girls she is friends with. He never notices she does this with every one and thinks she is flirting back. With me on the other hand I think she likes me as I get treated differently then every one and the friends we hang out with have called us out on flirting. Her best friend has even trying to set me and her up.

she is leading him on without knowing it and it makes the situation worse between me and him. I thought about getting her to stop doing things back so he doesn't get lead on/ hurt but he won't take it as me doing that. If I ask her out like her friend suggested and he finds out he is going to be hurt. I know he will never ask her out. If I don't ask her out to spare him, I know I will resent him somewhat for making me miss this chance with her. However I know there is another girl he likes and who likes him back, would it be wise to encourage him to go after her?
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+1 y
to add I think he missed his window he has known her about 6 months, while I have known who she is for maybey 2-3 months but only really talked to her and hung out for the past month. I don't want to miss my chance with her because of him either
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+1 y
I would apreciate real answers not "bros before hoes" or "fight to the death" cause that won't solve the situation
Best friend and I like the same girl, what now?
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