How can you tell if a guy really is in love with you because your boyfriend says he loves you but sometimes you don't know if he really does?

If he has beeen talking to u a lot and flirting with yai think u got a bf also if he keeps talking to ur m8s and then they come over to u he was talking about u hold on girl ur probably still really young im 11 and never had bf they come out of the blue believe me I am 13 and I have never ever had a boyfriend