Hi@akhtar,
The following create-service example shows how to create a service called ecs-simple-service with a task that uses the EC2 launch type. The service uses the sleep360 task definition and it maintains 1 instantiation of the task.
$ aws ecs create-service \
    --cluster MyCluster \
    --service-name ecs-simple-service \
    --task-definition sleep360:2 \
    --desired-count 1