Add-on which addon can get an access token ?

[Catmes]

hello, hi guys. I'm learning about index API and don't know how to "get an access token" through page https://developers.google.com/search/apis/indexing-api/v3/prereqs#oauth
I'm not good at programming and I'm looking for an addon that can do this.
Sorry guys, maybe I'm confusing because I don't have knowledge of a programmer.
Thanks for all