Dm'ers, How can I be confident in Dm'ing?

Hello. I played my first game last year and we had so much fun even though we lost XD and made new friends. A bunch of my friends told me that they never play and they are interests and they really want me to DM since i have the most experience (even though i told them i played only one XDXD). I told them I will think about it, but in reality, i am scared. I don't know if they will enjoy as the way I did. I told my friend who DM'ed my game and he told me prepare a bit in advance and go for it. So far, i did a map.

I want to DM for my friends that i know them for so long, but i am afraid that they will hate DnD because of my English being bad and that i dont entertain them well. What can I do? How can I be more confident?