To use any of the above modules, you need to connect your Google account to Integromat. If you do not have a Google account yet, you can create one here. Note: YouTube does not provide any interface for downloading videos.
To connect your Google account, follow the general instructions for Connecting to services. After you click the Continue button, Integromat will redirect you to the Google website where you will be prompted to grant Integromat access to your account:
Here, allow access by clicking the Allow button. Afterwards, you will be redirected back to the Integromat administration page. Now, you can continue creating your scenario.