can you promote your business at the airport i am i travel agent and would like to promote travel at the airport

Of course, for a price usually. Call airport administration for details.

Call the airport business office and inquire about promoting your business. You can call Mitchell's General number and ask for their business office.

It the easiest place I been

Yes, you can rent advertising space.

You probably must rent a space. Calling and inquiring would be a very logical start. Good luck.