My foreskin is cracked and has painful vertical splitting on the skin, how can i cure and prevent this, its not an std, thanks.?

Hmmmm: Doesnt sound like an std but no guarantees. It sounds like some sort of an irritation such as friction without proper lubrication, or more likely, from applying some type of gel, lotion, soap, etc which severely irritated your skin. I would recommend only using aquaphor or shea butter cream to the area for a few days and avoiding any other activity until resolves. See dr. If not better in 5 day.

Phimosis: This sounds like "phimosis" which is the development of scar tissue on the foreskin of uncircumcised men. It cracks and can bleed when attempts are made to retract the foreskin. Treatment involves keeping the area clean and dry, topical steroid cream, and if severe or progressive scarring is present, circumcision. A physician should examine you to establish the diagnosis.