For modelling purposes, armatures can get in the way as you make changes to an object in Blender. Thankfully there’s an easy yet somewhat unintuitive way to remove them, let me show you how to do that.
It helps to understand how armatures come into existence in the first place, and knowing that it’ll make perfect sense how to remove them. When we rig an object in Blender, we create the mesh, then the bones (or the armature), and finally we parent the object to our armature with weights. This makes it become deformable. So the process to tie the two together is by parenting.
To remove the armature, select your mesh, then hit ALT+P and clear the parent/child relationship. This will make the mesh and the armature separate objects again.
You now have a mesh ready for re-modelling, and an armature you can delete if you no longer need it.