Don’t enjoy sex but I want to.

I have a really hard time enjoying sex with my partner. And I don’t think it’s his fault. I’d probably feel that way about sex with anyone. I love him so much and I love kissing and teasing but the initial act of sex just always makes me zone out and it’s not pleasurable. I don’t want to tell him because I don’t want him to think I don’t want to have sex with him like ever. And I want us to be able to have a healthy sex life because I know it’s at least enjoyable for him. It’s like I always want it but then when it happens I’m never satisfied? I don’t know. How can I fix this problem?