By changing the orientation of a worksheet to Landscape mode, you're making the page wider than it is tall, so more columns can be viewed on a single page. This orientation effects the on-screen ...

Learn how to change default Excel worksheet direction from right-to-left using Settings, Local Group Policy Editor or Registry Editor.

Then change the orientation to landscape using the Page Layout menu. After changing the orientation, right-click on the sheet name (any worksheet in the group) and select Upgroup Sheets.