How to bulk rename rows in Excel?

Question

excel

There is a file with 99800 lines. in two columns there are links to sharefile with names like:
CSHH100
CSHH101
CSHH102
CSHH103
CSHH104
CSHH105
CSHH106 etc.
you need to add the .xls file extension at the end ...
How can I do this? \u003d CONCATENATE is not suitable, I need it on the same line, apparently I need to write a macro, but I am not good at this, please help

Answer 1

Sub InsertStuffAfter()
Dim cell
For Each cell In Selection
cell.Value = cell.Value & ".xls"
Next cell
End Sub
UPD: found, issue closed

Answer 2

And you can also "link" in any free column, and then insert "values" into the desired column.