Set DNS and Default Route in PFSense from Console

Permanently? Not so easy. Temporarily, easy.

echo "nameserver x.x.x.x" > /etc/resolv.conf
route add default y.y.y.y

Where x.x.x.x is your DNS and y.y.y.y is your gateway.

Once you’re in the GUI, fix up the settings properly and you’re good.