You will need to have someone experienced in probing snakes to probe it to know the sex.
Lighting is not required for corn snakes but you can put a low watt energy saving bulb in for viewing purposes, you will need to guard this. Most people use led strips for this, no heat or breakage risks.
Heating on a thermostat is required, a heat mat will be fine for a corn.
Have you provide the snake with various hides? There are required but it will often create it's own.
How old is the snake?
Feeding young snakes once a week will suffice, on any prey. Once they start to reach adult size and age once every 2-3 weeks on a jumbo mouse will be fine.