How to orgasm?

Geri • Reece Simpson👫
Ok so, I've had plenty of clitoral orgasms and they are amazing but, I've always wanted to orgasm through intercourse. I have never been able to, I'm not a slag but I've had a few sexual partners and I'm not settled down with my boyfriend who I'm so happy with. He keeps trying to make me orgasm through sex and for some reason I just can't! Sometimes he will go that deep I feel like it's in my stomach and I et scared rather than letting him Carry on I instantly without even realising pull away from him this happens in doggy. 
Help me ladies! I really want to orgasm :( also my boyfriend would be so happy to be the first and of course last person to make me orgasm cause he's the love of my life🙉🙈