There is this guy that really likes me but he is 10 years younger than I am! Should I even give him the time of day?

I'm about to be 30. He is 20 but will be turning 21 in a few months. He is very kind, respectful & caring. I feel like he's very much into me & has been for about 2 years. 2 months ago he kissed me for the 1st time ever. It felt right. We have been talking ever since. He has told me that he's in love with me. I told him no way bcus of the age difference. He insists. Sometimes I do wonder if it'll work out or not bcus he shows me love but at the same time he has his immature moments (obviously he is only 20 yrs old). Should I just walk away or will I be walking away from a great guy? Being the woman, it's more awkward being older than the man. Uggh I really am confused.