You have 2 options generally:
* platform as a service or PaaS: Render.com, Heroku, etc. Expensive and less control, but it's actually ready to use and you don't have to do any DevOps work.
* normal clouds with whatever flavour of Docker-based deployment system they have: AWS Fargate, Azure App Services, etc - potentially cheaper and gives you more control but you need to know DevOps basics and at least provide a Dockerfile.