I’ve given you a screenshot of the method, click to enlarge it to view
First select the cell you want to modify the format; press the shortcut key ctrl A to pop up the "Set Cell Format"; select "Number" "Customize" in "; then select "0" in the type; change 0 to 0000-0000-0000-000gt; click OK and it's OK.
If you have any questions, please ask. If the answer is difficult, please accept it