(1) Open Google Apps Script (https://script.google.com/home).
Click on “+ New project“.
(2) Rename project name to “Custom Sheet API“.
(3) Remove default code from the editor & Copy-paste our provided code there.
Don’t forget to put your google sheet ID in that code. You can get sheet ID from the sheet URL.
(4) Click on a save project icon and then after click on “Deploy” button. Here select “New deployment”.
(5) Now choose “Web app” as select type. If you want you can change description. Choose Web app Execute as: Me & Who has access: Anyone. Then click on the “Deploy” button.
(6) Now authorize access screen will be displayed like below. Click on it and select your google account.
Now Google hasn’t verified this app warning will be shown. Click on Advanced and then click on Go to link. Then click on “Allow“.
(7) Now you will see the deployment details like Web app URL as shown in the image below. Here copy web app URL and click on “done” button. That’s it.