
When collaborating with people on Google Sheets, Locking certain cells is an extremely useful tool. I will show you how to do so in just a few easy steps.
Step #1: Access "Protected Ranges"

Right click the cell that you want to protect. Then, in the drop-down menu click on "Protected Range". That will take you to the "Protected Sheets and Ranges" menu
Step #2: Name It and Set the Range

In the "Protected Sheets & Ranges" menu, you will fill in the name and range of your locked cell. The range should already be there if you right clicked the proper cell. Then you will click on the green "Set Permissions" button.
Step #3: Set Permissions

Here, you will be able to control who can and cannot edit the cell. you can also manually add new email addresses to your "team" of editors.
Step #4: Verify That it Works

Lastly, you should test your protections by trying to edit the cell from an email account that is restricted.
If the account is properly restricted, nothing will happen to the cell and a notification will appear and inform you that the cell is protected.
That is how you lock, or protect, cells in Google Sheets.