Windows supports having many network interfaces, for example you could have both wireless and wired Ethernet on the same laptop. Each of those would be its own network adapter. It's also possible to have more than one of each type, say two Ethernet ports, which might be useful on a server.
Normally you would only connect one at a time. Say you are connected to wireless, you probably would not also connect your wired interface by plugging a cable in. In this case, you would see
Media disconnected under the
Ethernet adapter Local Area Network, as you do see in your screenshot.
In addition to these hardware interfaces, there are also software interfaces. One common use for these type is with VPN software. These interfaces do not exist in hardware, but you can send data to them just the same, and what happens is defined by the software. A VPN would take the data and encrypt it before sending it to another interface.
192.168.56.1 interface is named
VirtualBox which leads me to conclude it is a software interface set up by the
VirtualBox software, for the purpose of creating a "fake" network between your "real" computer and the "virtual" computer. This means your "real" computer has a software interface with the address of
192.168.56.1 and the "virtual" computer has some other address on that "fake" network, probably
192.168.56.2 or something.
The FTP server ties into all this because it "listens" for connections on every interface you have at the same time. You have an IP address on a wireless network as
192.168.1.3 and you also have an IP address on a
VirtualBox software network as
192.168.56.1. The FTP server does not know/care which one is best; it just listens on both of them.