I have feelings for a guy since4months.he told me he likes me,itook it for a joke.iwant to know if he meant it

it has been 4 months since i felt attracted to thisguy, he told me likes me i took it for a joke. i think he really meant it but now we act as friends but sometimes he flirts.i'm tired & i want to get it over with.how can i correct the situation?i can't be friendswithsomeone i like.i don't know if he's punishingme or what. how can i explain to him without being rude that it's either to be a couple or we can't be friends anymore?