Insert multiple rows or columns into an Excel spreadsheet
Method (see video above)
Highlight the number of rows or columns that you want to insert in the relevant location in the worksheet, by clicking and dragging from within the worksheet row and column labels (i.e., the first column containing the row numbers, or the top row containing the column letters).
Right-click and select Insert.
The new blank rows / columns will be inserted above / to the right of the first row / column in the range that you selected.