It depends on how old you are. My SO is 9 years older than me, but we met when I was in my late twenties.
On the other hand, when I first started dating (at 15-16), a couple of guys in their 20's asked me out - and that is sick! Once you get into your twenties age isn't such a big factor, but if you are in your teens it is. Not to mention if you are under 16, in a lot of places it can be illegal.
I just looked at your profile - you are 14, right? So the guy is 18? He is a legal adult, and I would seriously question him if he is interested in a 14 year old.
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