Its best to think of it as populating elements parameters; the schedule is just Revit’s table displaying those parameters, so really any topic on the forum relating to Excel data to Revit parameters will be helpful to read into.
Here are a couple of links that should be useful:
If you think there is something specific to how your wall data is managed, feel free to drop a sample .rvt with some walls and your schedule format and I could provide better direction