No. Only one 10/100Mbps Ethernet port.

You can use several AV500 powerline adapters (this product is a starter kit). Starting from the router, you can continuously use the powerline adapters wherever you need internet and have a power socket. To add a new powerline adapter to the network already set up, simply press the "Pairs" button on the device or alternatively use TP's own utility app.

Yes 2 cables also from the original boxes

I only use 2 plugs myself, so I cannot answer the question from practical experience. According to the manual, the network can be extended to additional nodes. It is only important to note that all plugs must be provided with the same password so that they can connect.