if you have spokes, you have tubes. That will need to be removed to repair or replace the tube. The tire probably says "Tubeless" but there's s still a tube in there if you have spokes.
If they're truly tubeless, you can try a plug while still mounted on the bike.
"how" is going to need a lot more information for anybody to help you, starting with what kind of bike you have. You mention removing bags so I suppose we're discussing a rear, and yes, you'll probably need those out of the way to get the wheel off. The basics will involve getting the tire off the ground somehow, wood is usually good piled under the frame. There's an axle through the center of the wheel that has to be removed, with a nut on the end and probably some spacers on each side of the wheel that will need to be put back in the right place on re installation. Maybe a cotter pin holding the nut in place. The chain or drive mechanism and brake may need special handling, once we learn what you have.
All of this should be in your manual.
Last edited by Idahoser; 07-24-2014 at 09:27 AM.