Example of getting the contents of a Google Doc via the Google Drive REST API in javascript.
let fetch_url = `https://www.googleapis.com/drive/v3/files/${fileID}/export?mimeType=text/plain`;
let folder_fetch_options = {
method: "GET",
headers: {
Authorization: `Bearer ${token}`,
"Content-Type": "application/json",
},
};
const response = await fetch(fetch_url, folder_fetch_options);
// Text will be a string representation of the Google Doc
const text = await response.text();
For other Google Drive API Examples: https://www.mikesallese.me/tags/google-drive-api-examples