Google changed policy and requires developers to pass unreasonable verification process to get access to API for uploading. Unreasonable means that they basically want to get access to copyrighted source code which can be then hacked or misused for AI training. Furthermore, the verification process is so complex and difficult that it may take 100 work hours without guarantee that you will pass it. It may also cost 500$+. I am not able to get over this step. (you can gooogle it "reddit CASA Tier 2 certification for Google Drive" on Reddit)
The alternative solution is to create your own app which will work in a limited mode.
Go to https://console.cloud.google.com/
Press "Select a project". Press "New project".
Fill "Project name". Press "Create"
Select your project.
Press "View all APIs".
Find "Google Drive API". Then enable it.
Press "Create credentials".
Select "Google Drive API" and "User data". Click "Next".
Fill "App name", email, contact information. Click "save".
Press "Add or remove scopes", filter "Google Drive API", check "drive.file" and "drive.readonly". Press "update" button (scroll down). Click "save".