Explanation:

Box 1: Custom connector
While Azure Logic Apps, Microsoft Power Automate, and Microsoft Power Apps offer over 325+ connectors to connect to Microsoft and non-Microsoft services, you may want to communicate with services that aren't available as prebuilt connectors.
Box 2: Microsoft Dataverse
The Microsoft Dataverse connector provides several triggers to start your flows and many actions that you can use to create or update data in Dataverse while your flows run. You can use Dataverse actions even if your flows don't use a trigger from the Dataverse connector.
Use the Microsoft Dataverse connector to create cloud flows that start when data changes in Dataverse tables and custom messages.
Reference:
https://docs.microsoft.com/en-us/connectors/custom-connectors/
https://docs.microsoft.com/en-us/power-automate/dataverse/overview