How to move specific content between columns

I'm cleaning & preparing a large data set for use in ArcGIS approx 13k rows. The data set includes two different types of addresses: PRIMARY & MAILING address.

I would like to REPLACE any BLANK primary address entries WITH mailing address info.

Previously, I have done this by hand. Manually sorting data set for blanks, and then copy/pasting them into the primary columns.

I am wondering, is there an easy way to do this?

I attached an example of what the data set looks like. You can see the PROVIDER ADDRESS cells are all blank, and the MAILING ADDRESS cells all have data.


THANK YOU FOR YOUR HELP!

YES, that's what I was missing. THANK YOU

IF I use this on filtered data, will it effect ALL the data? Or only the filtered rows?