NewBie question - selectively delete email addresses with a specific domain

Need help with filtering data in columns & rows with specified email addresses.
Ideally, I’d like to remove all the email addresses within column Email Address, and replace it with a genuine personal email address from an adjacent column Email1 (not shown in screenshot).
The step in this screenshot doesn’t seem to be doing anything?
Pls advise.

@Mark_Berry Not a newbie question at all. If I’m understanding correctly, I’d use the Add if/else column step to create a new column with that logic (included one row of sample data to give you a sense of what I mean). The Filter rows step will get keep/remove any rows that match whatever criteria you provide, but I think the if/else step is actually what you need. See below for how I configured!