Using Android phone for network access on FreeBSD

Simply load urndis module
# kldload urndis

Connect mobile phone using USB cable with FreeBSD machine. On phone choose "USB tethering" for USB. On FreeBSD machine there should appear new network device ue0 or something similarly named. You can use for example dhclient ue0 to pull IP address for that device and then you can configure routing to use that device as default route.

N.B. If you prefer to use other DNS servers from what mobile provider is offering don't forget to modify /etc/dhclient.conf by adding for example:
interface "ue0" {
supersede domain-name-servers 1.1.1.1, 1.0.0.1;
}

Two above are CloudFlare's, or you can for example use some from OpenNIC for free for use, free from tracking and free from censorship DNS servers.