1)Set two adapters

Make sure the virtual machine is powered off or the Setting/Network/Adapter would be grayed out.

(Reference: https://superuser.com/questions/732999/virtualbox-cant-add-2nd-adapter-to-network-for-vm)

2)Adapters

Nat / Nat Network lets you online

Host-only Adapter Lets you communicate between virtual machines.

3)Mouse disappear

close Input / Mouse Integration

4)Mouse will not come out virtual machine

command + (click mouse left side)

5)Screen is small

Device/ Insert Guest Additions CD Image