Blow job

Not saying that I think it's gross or sth, but because I've never done it, n wonder how it feels... 

I have many friends who've done it n say "oh it's no biggy, u should give it a try." 

Me n my bf have been dating for 5 months, and we have sex every once or twice a week... I've been getting more n more comfortable wiff him now, it's just he's been asking me if I wanna try to give him a blow job. I'm kinda scared and at the same time feels bad since he lick me a couple of times w/o hesitating.