Im Not ready!!! I think?

Al

So I've been dreading the moment when my boyfriend would ask the question of " can we do it?" And he finally asked it....I'm kinda scared and embarrassed? If those are the words.this would be my first time and I'm just unsure. It's not like I'm not ready, I actually like him, he's a nice person, we've been together for 2 years I'm just not...ready? Girls I really don't know what to think or do!!! Can I get some advice