I hope there is no pressure on you to feel certain about your feelings of attraction. If anyone (including yourself) is putting pressure on you to do that, kindly remind yourself that attraction is a fluid thing, sometimes it can be very mysterious what it is we find attractive about another person, and it sure is an adventure just to explore those feelings. That doesn't mean you have to be in a relationship to explore those feelings. You are already experiencing them, so you can explore them if you want. But kindly remind yourself there is no pressure to have it figured out. You'll probably learn a lot about what you're feeling if you give it time. Deep breaths.
I feel like I need to be certain. I mean I like him a lot and we have been talking for awhile now but I’m scared I’m just in denial and going to hurt him because I’m not 100% certain
Certainty is just unattainable considering the gamut of emotions that we feel as humans, and that's okay.