Cannot get access token

I'm getting very stuck trying to get an access token in order to embed a PowerBI report.

The report in PowerBI https://app.powerbi.com/groups/me/reports/80106298-cf83-480a-aba4-c679ffac1535 

1. Is the  report ID 80106298-cf83-480a-aba4-c679ffac1535?
2. How do I find the Group ID?

I'm using the PowerBIEmbedded_AppOwnsData sample.

  <appSettings>
    <add key="webpages:Version" value="3.0.0.0" />
    <add key="webpages:Enabled" value="false" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />

    <add key="authorityUrl" value="https://login.windows.net/common/oauth2/authorize/" />
    <add key="resourceUrl" value="https://analysis.windows.net/powerbi/api" />
    
    <add key="apiUrl" value="https://api.powerbi.com/" />
    <add key="embedUrlBase" value="https://app.powerbi.com/" />
    <add key="clientId" value="Client ID from registering" />
    <add key="groupId" value="1" />

    <!-- The id of the report to embed. If empty, will use the first report in group -->
    <add key="reportId" value="" /> 

    <!-- Note: Do NOT leave your credentials on code. Save them in secure place. -->
    <add key="pbiUsername" value="My Azure Username" />
    <add key="pbiPassword" value="My Azure Password" />
    
  </appSettings>

 Should I be replacing the Authority URL with the OAuth 2.0 Authorization Endpoint in my Azure AD's Registered Applications properties?  (https://login.microsoftonline.com/{tenancy_id}/oauth2/authorize)