Insert or delete cells, rows, and columns

Insert or delete a column

To insert a column, select the column, select Home > Insert > Insert Sheet Columns.
To delete a column, select the column, select Home > Insert > Delete Sheet Columns.

Or, right-click the top of the column, and then select Insert or Delete.

Insert or delete a row

To insert a row, select the row, select Home > Insert > Insert Sheet Rows.
To delete a row, select the row, select Home > Insert > Delete Sheet Rows.

Or, right-click the selected row, and then select Insert or Delete.

Insert a cell

Select one or more cells. Right-click and select Insert.
From the Insert box, select a row, column or cell to insert.

Source: Microsoft