Yes. Sometimes women will ovulate more than one mature follicle or egg during a cycle, making fraternal twins possible. An embryo can also split, making identical twins.
Yes, you may. Identical twins are a fluke of nature and have nothing to do with ovulation, faternal on the other hand you would need to ovulate two eggs.
Yes! you can ovulate and concieve twins but that is if you have a trend of twins in your family. If you don't then its better that you get an insemination done as the docter will then help you to get twins.