Yeah this seems strange, I don't understand why you can't do it.
Sex is very simple. Erect penis is inserted into the vagina.
If you haven't done it before i suggest missionary position - man on top of woman. As in woman spreads her legs & man lies between with his erect penis. Use your finger if you need to help with the angle in which the penis is inserted. Let ur partner insert his finger to ur vagina so he can feel the angle too. Make sure his penis is lubricated & it will also help if you are sexually aroused as this will cause your vaginal area to become "wet" too which will help to make the penis enter your vagina more smoothly.
Without giving a "how to have sex" post... the man should then push his penis in as far as is comfortable then withdraw it either totally or until it is almost totally withdrawn then push it back in again & so on usually get faster & deeper as the act goes on.
This should work, otherwise could you please provide more details as to what the problem is.
it is difficult to help because I don't know what is going on. Is the male erect? Are you lubricated enough? What position have you tried?
dunt know cantunderstand...i guess cause of the position???can u help me??
why can't u do it? what is preventing you?