Being eaten out for the first time.

I'm 18, I've been with a guy for 4 months now he is 19, we had sex a couple of times, I've had two sexual partners before him, they never went down on me, I've never had an orgasm from sex, I've always been concerned about what I smell/taste like so I haven't let anyone eat me out, the guy I'm dating right now is persistent about making me cum and wants to go down on me, what are some tips you can give me about being eaten out for the first time? I'm really insecure about what my lady parts will look/smell/ taste like. What if it smells/ tastes bad 😰