@vikash ranjan Sorry for the delayed response. Just to confirm, are you following this documentation to Create a video analytics - object and motion detection application in Azure IoT Central (YOLO v3)
You can configure media graph by connecting components, or nodes, in the desired manner. You can manage media graphs via two concepts – "graph topology" and "graph instance". A graph topology enables you to define the blueprint of a graph, with parameters as placeholders for values. The topology defines what nodes are used in the media graph, and how they are connected within the media graph. For more details, please refer Media graph topologies and instances and see if it helps.