Before you can connect to Google Sheets what you will need to do is enable API Access for Google Sheets. This involves logging on to Googles Cloud API console and enabling the API for google sheets and google drive. Once you have completed this step you can then create a OAuth client id and client secret so that your users can authenticate to your application using OAuth.
Google didn’t make this step super easy but basically once you have created a new project (let me know in comments if you would like to see how to create a new project), you then need to open the APIs & Services page and select Library.
This brings up a page with all google API services.
Run a search for sheets
Once you select Google Sheets API this will bring up the enable API page.
Clicking on Enable will enable the API for use.
I then repeated the process for Google Drive and you can repeat this process for any API you would like to connect to.
In my next post I will show how to create client credentials for google OAuth so that you can connect via a web application.