To insert multiple page breaks simultaneously in Excel, follow these steps:

1. Open your Excel spreadsheet and go to the View tab in the ribbon.
2. Click on Page Break Preview in the Workbook Views section.
3. Your spreadsheet will now be displayed in a different view, with blue lines indicating where page breaks currently exist.
4. To insert additional page breaks, simply click and drag the blue lines to where you want the new page breaks to be.
5. You can also use the Insert Page Break button in the Page Setup section of the ribbon to add new page breaks.
6. Once you have added all the necessary page breaks, you can exit Page Break Preview by clicking on Normal in the Workbook Views section of the ribbon.

Using Page Break Preview allows you to insert multiple page breaks at once, saving you time and effort.