White substance almost like wet tissue paper under clitaous hood. how can i determine that this is yeast or smegma? do i see a doctor?

Probably no need...: If having no local symptoms, the white substance most likely represents the normally expected smegma which is the accumulated debris of shedding-off skin (desquamation) like that between glans penis & foreskin in men. Usually, it bears no clinical consequence but advisable to have regular gentle cleansing every so often although occasionally inflammation or yeast infection may superimpose. So, ask