Chances are it is a male. You only have one? (I know you rescued)

If you would get an egg without a partner pigeon it would of course not hatch anything.
One way to see if you have a male;;;; You would have to bring in a known male into cage. (from someone that keeps pigeons)
If they start fighting, it is a confirmed male. Two females are not likely to fight.
If you are going to keep as pet since you rescued, it should not matter M or F.
If you are interested in raising pigeons, then you would need some larger loft facilities to do it successfully. I keep pigeons myself, but currently have none. (long story)
I can answer most of your pigeon questions or direct you to those that can.
WISHING YOU BEST........