Open the Excel spreadsheet
Click the Review tab
Click Protect Sheet
Enter a password if desired
Select the allowed actions
Click OK
Re-enter the password if prompted
Save the workbook
To lock the workbook structure
Click the Review tab
Click Protect Workbook
Choose Structure
Enter a password if desired
Click OK
Re-enter the password if prompted
Save the workbook
To lock specific cells only
Select the cells you want to keep editable
Right-click and choose Format Cells
Click the Protection tab
Uncheck Locked
Click OK
Click Protect Sheet from the Review tab
Enter a password if desired
Click OK
Save the workbook