 To insert or delete a column, left click on a column to select it, then right click to open a menu and click Insert. Excel will insert a column to the left of the column you selected and move everything else to the right. To delete a column, select the column with a left click, right click again and then select Delete and the column you selected will be deleted. To insert multiple columns, left click a column to select it and then drag to select the number of columns you want to select. Here I've selected four columns. Right click and click Insert and you can see that Excel inserted four columns to the left of the leftmost column selected. To delete multiple columns, select the column and drag to select all the columns you want to delete. Right click and click Delete. Excel will delete the number of columns selected.