If you select bridge, the virtual ethernet adapter will behave as the host machine didn't exist and if it's configured to take his IP with a DHCP, it will get this IP from a DHCP server on the network.
Alternatively, you can attach the VM to directly network by sharing the network adapter from the host system as a bridged network adapter. In this configuration, the VM gets its own IP address, usually using your network’s DHCP server. The VM appears on the network the same way a physical computer would with its own hardware MAC address.
The host’s network adapter is shared by a device driver that is installed by (VMWare|VirtualBox). The VM’s virtual network adapter can only be bridged to one physical network adapter at a time. If your system has more than one network adapter you need to choose which one to attach to. If your system switches between wired and wireless connections, you will need to switch bridged adapters for the VM.