iPad 1 does not have a camera and there is no way to add one
tp the iPad. You have 2 choices: stay with iPad 1 without camera
or update to new version with camera.
If you are near an Apple store or Apple authorized retailer, take him
in so he can play with a newer model - that might change his mind
about upgrading. Or have a friend with a newer iPad visit your father
and show him what he is missing.