Okay, so i know this guy......(advice needed)?

so i know this guy who goes to my school, he wanted me to meet him tonight and to wear a skirt, but i didnt go, he said he wants to meet me another day, i want to go but i know he wants sex, he said we can be shag buddies, i feel ready for it but i'm not sure, some advice would be nice, how old were you when you lost your virginity and i would obviously use protection! thankyou!