Navigating Between Excel Worksheets and Files
Here is one area of Excel (like many others) where it’s far more efficient to use the keyboard than the mouse. Here are the basic shortcuts for moving between worksheets in a file, or between files. These shortcuts will also work when creating a formula.
CTRL + Page Dn: Move to the worksheet to the right (best to use the right CTRL key)
CTRL + Page Up: Move to the worksheet to the left (best to use the right CTRL key)
CTRL + Tab: Move to another open Excel file (best to use the left CTRL key)