You can't change money when playing stand-alone games. You can't give it to anyone, but you can use the secret: press Enter and enter "greedisgood+ space+the amount of money you want". In this way, the computer will get as much money as you.

You can give money to the computer when you play on the LAN, but you can't ask the computer for money, because the computer can't tell when you need money and can't talk to it.