@GlitchMorningstar ooh this sounds nice! maybe since he's in a rough place rn uu will have to first wait for it, no worries, it'll never be too late to confess but first give it time! <33
maybe try to have a conversation w them, make him mini compliments, tell him about cutesy stuff that you both enjoy!
i'm sorry if it's not much, i don't really have experience on what to do with ur crush even as someone in a (poly) relationship...
nonetheless, remember to not just love them, but also love yourself <3
remember that uu are loved. after waiting it out for them, no matter if the outcome is bad or good, you've made yourself the courage to tell him that you like him<33