I'm having folic acid iron and vitamin b, is it okay to have a vaccination for anti cervical cancer prevention? Whats the effect for pregnancy?

The HPV vaccine. Is usually given to adolescent girls (and boys) to prevent transmission of the viruses causing cervix and other cancers. It likely has not been tested during pregnancy, so it may lack proof of sfty to developing embyo/fetus. The vitamins are not an issue for either.
Don't do it. Apparently there's no effect on the fetus with this that is thus far known however, this is a new vaccine and data on it is very limited, so if you didn't get it yet, the recommendation is not to get it until after your pregnancy. As for your folate (folic acid) and vit b, that's definitely good for your pregnancy. Best of luck.