Is it possible to send/receive via QT but my port 8333 is not accessible?
Yes.Just because bitnodes is unable to connect to your node does not mean that your node is offline or not connected to the network. That website only knows about nodes which accept incoming connections. It is likely that your node does not accept incoming connections (i.e. your router or something else blocks incoming connections to port 8333). Your node can still make outgoing connections and connect to other nodes so you are still connected to the Bitcoin network. Even with just outbound connections, you are still contributing to the network as you are still receiving, verifying, and relaying all blocks and transactions.
