(Since this appears to be a question rather than a (finished) project to showcase I’ll be moving the topic and switching around two words in the title)
When you say projects, do you mean the Node-RED Projects functionality, or code in different flows? As for Projects, it’s not possible at the moment to have multiple projects active in the same node-red instance. You can work around that by starting an instance for each node. That still leaves the issue of different ports, but you can resolve that by setting up a reverse proxy (e.g. nginx), then place each instance on its own path in the configuration there.