at a base, you can use heroku. That said, you won't be able to have your nodes communicate with each other. This restricts you from some of the more advanced featues. For Example, at my startup, we use horde to dynamically spin up individual websocket connections per customer for a integration partner. This was easy to do using horde and simply connecting the nodes together. Additionally, we can use the built in key store which is global to the cluster.

I would take a look at render.com. they support connected nodes and autodiscovery