In a shared spreadsheet, the protect feature enables you to protect your important data that you do not want anyone else to change.
Execute following steps to protect sheets and ranges in Google Sheets:
1- For ranges to protect, select ranges A1:C1.
2- In the Data tab, select Protected sheets and ranges.
3- A panel on the right side will appear. Type description for reference and click Set permissions.
Note: To protect a sheet, click on the Sheet tab.
4- Click Done after setting range editing permissions:
i- Show a warning when editing this range.
ii- Restrict who can edit this range (available options are “Only you”, “Custom” and “Copy permissions from another range”.
5- You have set permission for the range A1:C1.