help with my camera

I need help with the camera on my macbook pro, i’m trying to talk with my husband in Iraq and we want to use the camera , but for some reason we can’t see each other or hear, he has a hp computer in Iraq, and not a apple like myself, i really could use some help we haven’t seen each other in a year now other then sent pictures, it would be nice to hear his voice again. thank you for any or all help with this problem Dianna