Here is the exact definition of all params in the task definition: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/task_definition_parameters.html

thanks you @ejoebstl. I give fargate another try. It is just that the length and complexity of the fargate yml file ,compared to my docker compose file, is a bit scary. On the other hand If I run it on a single ec2 instance I have to manage external ip/urls, vpcs etc I guess? I was just scared because it always takes me a lot of time to get things working on aws. I have used azure in the past which is much easier but has some limitations that force me to use aws

Sure, that's because you need a cluster, vpcs, security groups, an ALB and load balancers with fargate. Tbh this is also quite expensive. But I'm using the vpc setup for all business applications, because of the network level isolation of servers. Fargate is nice because you can scale seamlessly in production. Once you've figured it out, it's super powerful - what helped me a lot was to read through the documentation on AWS before even looking on terraform or cloudformation.