If you know anybody that has a rabbit dog that is your best chance. The best way for beagle to learn is from another beagle.
If this is not an available option then do as Bo Nose said. If you can get the dog to jump a rabbit he'll know what to do. When he jumps holler encouragement " get it dog! get it!".
The only reason you would lose the dog is if it jumped a deer and gave chase. A rabbit will make a loop back to where it was jumped as it tries to lose the dog. When the rabbit gets back to it's hiding place it will stop momentarily. When the dog keeps coming the rabbit will run the pattern again. A deer will run it's normal trails from thick cover to thick cover and not in any particular fashion.
If there are a lot deer in the woods where you will be hunting you might not be able make rabbit dog out of him.

Good luck Bro.