I've constantly been running into bevel issues, where instead of 'rounding' the selected edge, it is warping the surface, creating texture I do not want. I am currently using a Mac (shortcut I use for bevel is command+shift+b--command b does not do anything for me) and every tutorial I try out, I get stuck when it comes to rounding any corner or edge. Is there possibly a fix for this?
For the moment you can't bevel the edge because you have an inner face, the edge is common to 3 faces and therefore Blender can't guess how to bevel, once the inner face deleted, Ctrl B should work:
If you have a problem of shortcut, you can open the Preferences > Keymap and type "bevel" in the search field, then redefine the shortcuts you want for this operation.