My son is 15 and 6m, he has some leg hair but not entirely noticeable, and his armpits have only a couple hairs but they are darkish but not noticeable. i am 6 foot 3, his mom is 5 foot 4, and he is 5 foot 5. is he a late bloomer? how tall will he be?

Your boy's future height will probably fall between 69 inches (5'9) and 77 inches (6'5) based on parents' heights. You can estimate his future height based on his current height & age with a different formula but his current weight is required by this link - https://www.omnicalculator.com/health/height

Expected final height of males is the average of both parents plus 2.5 in +/- which would suggest a final height of 6'. A single x-ray of his wrist/hand can be examined for open growth centers, if they concur with your late bloomer label and show more growth potential than an average 15 yo he can reach the expected height or more. If the growth centers close, you stop growing taller.