The Landscape Portal acts as a central tool that allows you to perform lifecycle management operations, such as provisioning new consumers tenants, users, and more. See Landscape Portal.
As an operator, subscribe to the Landscape Portal application in the 05 Provide subaccount in both the global account for development and global account for production. The LandscapePortalAdminRoleCollection needs to be assigned to the users in the default identity provider of the subaccount that you want to provide access to the Landscape Portal app. See Accessing the Landscape Portal.
In the Landscape Portal, you can access the provider system and choose the provider tenant (client 100). Via the provider tenant, you get access to Fiori Apps, for example the Manage Software Components app, which is used for importing software components via gCTS.