When I add a Modifier, nothing happens When I click on wave in the modifier list, nothing happens. However when I click on the Subdivision Surface modifier this does work.

After I set the surface modifier to desired setting, and try to add a wave modifier, just the top of the object moves up and stays;nothing else happens.  

When I add the wave modifier only, with no subdivision surface modifier, nothing happens. When I click apply in the wave modifier box I get this message," modifier disabled skipping apply. How can I activate the modifiers?  How can I fix this?
You have actually selected the Warp modifier instead of the Wave modifier. 

For the Warpmodifier to work, you need to select two objects in the "from" and "to" dropdown menus.

If you have trouble with the Wave modifier, try adding more geometry like Samir Rahamtalla suggested (subdivision modifier before the wave modifier or manual subdivision in edit mode).

Further information (Blender Docs)