I'm APPlying for an llc and it says to put in registered agents number what is that and how do I get it?

Contact the licensing dept. where you are applying.

If you do business and get your LLC in a state where you do not live or have a office, you must have a registered agent, in that state normally. You pay a fee to a company that does this, to be your registered agent.

Normally in your home state, this is not needed since you will have a physical address in that state.