Reference:
https://docs.microsoft.com/en-us/azure/cosmos-db/create-cosmosdb-resources-portal

The Integration Runtime (IR) is the compute infrastructure used by Azure Data Factory to provide the following data integration capabilities across different network environments:
Data Flow
Data movement
Activity dispatch
SSIS package execution
Reference:
https://docs.microsoft.com/en-us/azure/data-factory/concepts-integration-runtime

Explanation
Power BI Report Builder is the standalone tool for authoring paginated reports for the Power BI service.
https://docs.microsoft.com/en-us/power-bi/paginated-reports/paginated-reports-quickstart-aw