What to do if i have phimosis don't wanna tell parents what should i do?

Treat it: You sound old enough to go seek and receive treatment on your own. This is not something to be embarrassed about. It's not like you have to tell them you crashed their car or something similar. Be treated and become comfortable!

Here are some ...: The care for phimosis is well known to almost all, and include implementing adequate topical care with/without using topical antifungal caream as palliative, temporary measures and circumcision as definitive care. As to tell your parents or not, that would be up to you at 37, but open and straight communication is still the best way of communication for maintaining a relationship.