SOS thrupple advice

So tonight my best friend and my boyfriend as well as myself tAlked about becoming a thrupple. They gave me complete control and I love them and am attracted to them both. But I’ve never really done something like this. I’d be having sex with both of them and we would have sex but they wouldn’t have sex with each other. I just need some serious help. I know for sure that I wouldn’t loose them if things went bad but it’s still a fear. I’ve never been with a girl so I can’t even say with confidence I’m gay but I feel certain I’m attracted to her. I’m so confused pleassseeee help me.