If a male perform oral sex to a female then just place his penis on her vagina. Then use condom can she get hiv?

Yes. Any exchange of genital bodily fluids can cause transmission of hiv. Ask your partner to get tested if you're worried. Better to be safe then to have lifelong disease because of a sexual encounter.
Yes. The virus goes from one warm moist place to another easily especially if exposed to a blood pool or the person is already infected.