How can I turn on the macOS firewall from a script

I'm setting up a new Mac Mini and I am using a script assembled from commands that I've accumulated over the years to set defaults, create directory structures, install software, and otherwise customize my Macs the way I want them. The first command--to turn on the firewall--is failing to do anything. How is the firewall currently turned on, in Catalina?

The command I'm using is

sudo defaults write /Library/Preferences/com.apple.alf globalstate -integer 1

This is the same thing I'm finding by Googling (or an alternate form with -int instead of -integer).

If it has not changed, what could be preventing it from working?

macOS now uses the pf firewall (from OpenBSD). Since Mac OS X Lion (10.7) circa 2012, the firewall ipfw was deprecated in favor of pf

The command to disable the pf firewall is:

% sudo pfctl -d 

For full command line options for pfctl see man pfctl.