Steps to format all Excel worksheets the same way:

1. Open the Excel workbook that contains all the worksheets you want to format.
2. Click on the first worksheet tab at the bottom of the screen.
3. Hold down the Shift key on your keyboard and click on the last worksheet tab. This will select all the worksheets in the workbook.
4. Right-click on any of the selected worksheet tabs and choose "Select All Sheets" from the context menu.
5. With all the worksheets selected, go to the Page Layout tab in the ribbon.
6. In the Page Setup group, click on the small arrow in the bottom right corner to open the Page Setup dialog box.
7. In the Page Setup dialog box, you can set the orientation to Landscape, adjust the margins, set the print size to 70%, and check the box to show gridlines. Make sure to click on the "OK" button to apply the changes.
8. Now, when you go to Print Preview, all the worksheets should have the same formatting.

That's it! You should now be able to format all Excel worksheets in the same way without having to change each one individually.