In Excel, you can protect a single spreadsheet with a password. The data in a protected sheet cannot be changed.
1. Select the Review tab:
2. Click on Protect Sheet:
3. Type your password into the box and retype it to verify. After that, click on the OK button. You can also grant more or fewer permissions to users of this sheet by checking/unchecking the checkboxes.
4. A protected sheet will appear with a lock icon as shown below:
5. To remove the password associated with the sheet, click on Unprotect Sheet on the Review tab then enter your password:
Done. Happy working!