oral sex

just some background info, ive been with my boyfriend for a little over a year now and everything is great. however, i don’t really know how to ask him to eat me out. he’s done once really early into our relationship for about 3 minutes and, i thought he was doing a really good job. but, he said he feels he wasn’t doing good so he got nervous and stopped. i dont want to pressure him at all to try again if it makes him feel so nervous but, i feel like i’m missing out a bit and i would really appreciate if he would do this for me.

how can i approach him gently about this? and how do i not feel super anxious about when/if i talk to him about it?