How to know if a guy likes you at 16?

my guy friend is my age and we have been friends for 3 years and for the first year I liked him the second year I was kinda getting over him but when we were in the stairs he would always stand close to me now we are not those type of friends that hangout after school we only meet each other at lunch and this year he is like an ok kinda person I don't know if he likes me or not the first year when I told him I liked him he didn't like me and I still think he don't like me in that way

How to know if a guy likes you at 16?
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