>>2946613 (OP)
to repair it you remove the tube and use glue and a patch* on the inner tube
to replace the tube you do the same thing but release the rear sprocket either with a wrench or quick release lever so you can work it around the not chain side of the rear axle
a wheel is the rim, a tire is the rubber part, the intertube the thing you float down a river on before getting stabbed by a boomer
the bead is the solid part of the tire that sits inside the rim channel. to remove the tube for patching or replacement you need to force one side over the rim. there are handly little plastic tools that are included in almost every amazon patch* or tube kit which are meant to assist with this, especially if you have baby hands. putting a very small amount of air in a new tube helps with reinstalling it. don't ever use tire sealant.
*modern quick patches are designed to fail after a few hours and are only meant to get you through a ride. as a kid we rode on patched tires for the life of the bicycle today you just have to get a new tube or constantly fuck with it.