Note: This feature requires a Creator or Professional plan
To obtain the information for your scheduled event, you'll want to visit your YouTube Events page and create a "New live event". On the next page set up your event, select Custom for your "Type" at the bottom right. and click "Create event".
Once you've created your event, select a stream key type from the following page and you'll see the Ingest Server (Primary Server URL) as well as the Stream Key (Stream Name)
You'll then want to import this information into an RTMP Destination as shown in the gif below: