In excel, how to I add a an external sheet to my current (or new) workbook?

You need to open both workbooks (or whatever workbook you want to copy from and to…)

activate the workbook to copy from, select the sheet(s) to copy and
click on > Edit >Move or Copy Sheet > Create a Copy
(if you dont click on create a copy… it’ll move it!)
and nominate the workbook to copy to from the pull down menu.

tada!

When does this work?

A user asks “I have 3 sheets on 3 diff seperate files, and I want to consolidate them into one workbook….”

tada!