Here's how you can do it:

• Select the Columns: Click on the letter at the top of the column you want to delete. ...
• Right-Click and Delete: Once your columns are selected, right-click and choose 'Delete' from the context menu.
• Save Your Work: Always remember to save your file after making changes.

Deleting Unused Columns

• Selecting columns First, click on the header of the column you want to delete. To select multiple columns, click on the first column header, hold down the Shift key, and then click on the last column header. ...
• Deleting selected columns Once the columns are selected, right-click on any of the selected column headers and choose the "Delete" option. ...