Can you get an std like hiv or hep c by contact with urine. i lifted a public toilet seat, and there was fluid, think it may be urine. had small cut ?

Highly unlikely.: Everyone uses public toilets throughout their lives, and people are generally less than sanitary in their usage. If diseases were easily communicable in this way, we would all be in trouble. Cut or not, the best thing for you to do is wash your hands thoroughly after each toilet use, and you will be fine. Unprotected sex is a good way to get both of these, however. Use condoms.