Tight Vagina with Thick Penis. HELP

I have sex before many times but it was with guys who have more of the average thickness/ skinny kind of dick which was totally fine.

But now I'm dating this guy and I've told him that i dont wanna have sex anymore or until marriage because I really see something with him that is pure and kinda wanna make it stay pure. Thats another topic. Even though that is one of my reasons, another reason is also that he has a very thick dick. Like too thick. So I'm scared of how itll be having sex with him since ive never had sex with someone who had a very thick dick. I know I'm really tight and I'm just scared of "stretching" and all that. I'm scared itll hurt much more. I dont know, can someone tell me their experience or something? Does it hurt with a thicker dick? What happens to your vagina? Does it stretch then go back to the same size right after? Or will it eventually get stretched out or "loose" ugh HELP😩

Do I sound dumb? Idk like a part of me really wants to have sex with him but I'm just scared of what will happen down there 😅

Okay thanks loves😚