Seriously.. What should I do now..

I have a really really big problem right now! 

It is start when my bestfried likes someone.. he is three years older than us. I always tease my friend and I really ship both of them.. I thought it will be so fun (yeah, because my friend never interest to boy) but then.. it turn differenly than I though..

The boy's friend suddenly told me that he likes me. And I really shocked! I do not know what to do? Should I tell her or what...?

I need your help huhu...