how to return two observable one after the other code example

Example 1: how to return two observable one after the other

GET https://api.powerbi.com/v1.0/myorg/groups/{groupId}/reports/{reportId}

Example 2: how to return two observable one after the other

GET https://api.powerbi.com/v1.0/myorg/groups/f089354e-8366-4e18-aea3-4cb4a3a50b48/reports/879445d6-3a9e-4a74-b5ae-7c0ddabf0f11