I had this question a few days ago: can we add tags to Revit walls?
This question come up because the user always automatically tag his doors and windows. Door tags can be placed automatically during door placement. But not for walls. For many type of objects, we need to add tags manually.
You can add tags or keynotes for your wall. The tools are in Revit ribbon>Annotate tab>Tag panel. For tagging your wall, you can use tag by category.
Tag all (not tag) can tag all objects in specified categories. However, wall is not a category you can choose using this tool.
Wall tags will show the value of your walls type mark. You can change it in the walls type properties.
If you do not want to show the wall type in your tag, you can show the material tags. The wall type should have the same interior and exterior finish. However, I know some engineers want to tag their wall finishes, not by the wall types.
If you want to add a material tag, you can find material tag in the same panel.
The value shown in your material tag is the material description that you use for the wall.
All of the tags will show your type properties.