Select the column or columns that you want to change.

On the Home tab, in the Cells group, click Format.

Under Cell Size, click Column Width.

In the Column width box, type the value that you want.

Click OK.

Match the column width to another column
Select a cell in the column that has the width that you want to use.

Press Ctrl+C, or on the Home tab, in the Clipboard group, click Copy
.
Right-click a cell in the target column, point to Paste Special, and then click the Keep Source Columns Widths Button image button

Regards,
Jerry