getting rid of a boy

there is this guys and he likes me a whole lot. but I don’t like him. and he keeps texting me and is very sweet but I don’t like him and he has never kissed a girl and he is older than I am and I am more experiacned than he is. and he asked me to be his first kiss with no strings attached. and I thought that it wouldn’t be so bad, but I don’t know if I do if that wil make me a slutt.

and I want to stop talking to him but wheni do he thinks that I am mad at him and it makes me feel bad like I am hurting him. and my bestfriend said that I should just stop tallking to him but I feel bad cause then he gets upset. and he tells his friends that I am a bit ch and sometimes they belive him and it gives me a bad rep. what should I do about these sittuations. and this is the same guy haha

HELP!!