the ports allow incoming connections from other nodes.  the bitcoind attempts to open those ports.  It pushes out to other nodes to connect using a master list in a node database.  Once established the bitcoind creates P2P node connections. At this time it opens the incoming ports.  If successful you will see your node count increase.  If your providers is blocking incoming connections it may be futile and at the mercy of your provider.  Some routers close the ports for firewall purposes which is why you log into the router to open the ports.

The most important thing for all apollo users to do is look at their log.  media/nvme/Bitcoin/debug.log.   It gives loads of information on the performance of your node and status.  You can see the connections made to other full nodes or block only relays.  You can see startup and shutdown sequences.  When the bitcoind node program starts up you will see the sequence of events including the attempt to connect to the outside world.  If it fails you should see the errors there.  Your node is constantly connecting to new nodes around the world on the P2P network(decentralized).  Adding and dropping connections.  In the node tab in the GUI you can see the different nodes and addresses your apollo is connecting to and these change over time.  What is fun is to see when you connect to another apollo node.

This log also addresses the question in a previous post about the node software using the system drive for bitcoin data storage instead of the nvme drive.  during startup it defaults to the system drive for bitcoin data storage files and then reverts to the nvme drive for bitcoin data when it is found.  Described in the logs.