I second the suggestion that you should add a NIC to the host. https://www.vmware.com/content/dam/digitalmarketing/vmware/en/pdf/support/landing-pages/virtual-supp...
However you can setup NAT and Routing so the VMs use either local networking or has an access to the Internet. nat - Setting up VMWare ESXi 5 with a single physical NIC - Server Fault