The Get-AzManagementGroupSubscription cmdlet gets the subscription info under a Management Group. Providing the SubscriptionId and GroupName will give only the Subscription details for that subscription. Providing only the GroupName will list the details for all Subscriptions under the Management Group.
Examples
Example 1: Get Subscription Details under a Management Group
Name : aaaa0a0a-bb1b-cc2c-dd3d-eeeeee4e4e4e
Type : Microsoft.Management/managementGroups/subscriptions
Id : /providers/Microsoft.Management/managementGroups/TestGroup/subscriptions/aaaa0a0a-bb1b-cc2c-dd3d-eeeeee4e4e4e
TenantId : aaaabbbb-0000-cccc-1111-dddd2222eeee
DisplayName : Visual Studio Enterprise Subscription
ParentId : /providers/Microsoft.Management/managementGroups/TestGroup
State : Active
Example 2: Get all Subscription Details under a Management Group
Name : aaaa0a0a-bb1b-cc2c-dd3d-eeeeee4e4e4e
Type : Microsoft.Management/managementGroups/subscriptions
Id : /providers/Microsoft.Management/managementGroups/TestGroup/subscriptions/aaaa0a0a-bb1b-cc2c-dd3d-eeeeee4e4e4e
TenantId : aaaabbbb-0000-cccc-1111-dddd2222eeee
DisplayName : Visual Studio Enterprise Subscription
ParentId : /providers/Microsoft.Management/managementGroups/TestGroup
State : Active
Name : 2120692d-35c3-44c8-81f5-631fa7351726
Type : Microsoft.Management/managementGroups/subscriptions
Id : /providers/Microsoft.Management/managementGroups/TestGroup/subscriptions/2120692d-35c3-44c8-81f5-631fa7351726
TenantId : aaaabbbb-0000-cccc-1111-dddd2222eeee
DisplayName : Test Subscription
ParentId : /providers/Microsoft.Management/managementGroups/TestGroup
State : Active
Parameters
-Confirm
Prompts you for confirmation before running the cmdlet.
This cmdlet supports the common parameters: -Debug, -ErrorAction, -ErrorVariable,
-InformationAction, -InformationVariable, -OutBuffer, -OutVariable, -PipelineVariable,
-ProgressAction, -Verbose, -WarningAction, and -WarningVariable. For more information, see
about_CommonParameters.