Windows Defender is not a firewall.
Don't let the OT discussion distract you. (Hard though it is.)
There are various sites around that offer a list of firewalls, some also offer reviews, (which of course are sometimes biased), one of the sites I find very useful for all sorts of security software is
AndyManchester.This one is quite useful, too. Just a couple of examples.
Popular firewalls that seem to work well with Avast include PCTools, OnlineArmour, Comodo, and of course the Windows firewall.