https://blog.canopas.com/complete-guide-to-deploying-ssr-vite-apps-on-aws-with-automation-27676113d6ac - ECS service

template-ecs.yml

AWSTemplateFormatVersion: 2010-09-09
Description: An ECS, ECR, ALB and cloudfront stack
    
Resources:       
   ECSService:
     Type: AWS::ECS::Service
     DependsOn:
      - HTTPListener
      - HTTPSListener
     Properties:
       LaunchType: FARGATE  #launch type is farget
       Cluster:
         Ref: "ECSCluster"  #ecs cluster reference
       DesiredCount: 1
       TaskDefinition:
         Ref: "TaskDefinition"  #task definition reference
       DeploymentConfiguration:
         MaximumPercent: 100
         MinimumHealthyPercent: 0
       NetworkConfiguration:
            AwsvpcConfiguration:
                AssignPublicIp: ENABLED
                SecurityGroups:
                    - !GetAtt ApplicationLBToECSSecurityGroup.GroupId #security group id
                Subnets: [<SUBNET-ID-1>, <SUBNET-ID-2>] #can add multiple subnet ids
       LoadBalancers:
            - TargetGroupArn:
                Ref: TargetGroup #target group reference
              ContainerPort: 3000
              ContainerName: < ECR-CONTAINER-NAME>