M365 Excel - Hide or show rows or columns

Hide columns

1. Select one or more columns, and then press Ctrl to select additional columns that aren't adjacent.
2. Right-click the selected columns, and then select Hide.

Unhide columns

1. Select the adjacent columns for the hidden columns.
2. Right-click the selected columns, and then select Unhide.

    Or double-click the double line between the two columns where hidden columns exist.