So there is really no risk here.
Touching each other penis - no risk at all.
Licking his feet - no risk at all for STDs. If he had any sign of fungus, that's a possibility, but please don't lick someone's feet if they have signs of a foot fungus.
Cum on my face some in mouth. - no risk at all. The semen in your mouth isn't because the risk from oral sex comes from either semen being deposited in the back of your throat (gonorrhea and chlamydia), or direct, skin to skin contact (syphilis). Neither of these things happened, so you're fine. There is no risk for other STDs, including HIV.
You do not need treatment, especially PrEP (which is before) or PEP (which is after, and what I think you meant), or antibiotics.
A really important point here - you and your wife are trying to get pregnant. If this happens, and you continue exploring, it is important that you control what happens, and/or use condoms. Exposing a fetus to an STD can be very dangerous at different points in development. No judgement here, just information.