Golf League Tracker has several options for handicaps, but there are some common settings which most leagues customize for their own use. This article describes what to change for specific formats.
I recommend using the GLT 2020 Rules with a Custom Score count.
In short, using the recommendation below, a player will establish a handicap after 2 rounds. Ongoing, it will take the most recent 6 rounds. It will toss out the high 33% of the score differentialss and use the remaining to calculate the handicap.
You can configure Golf League Tracker to use whatever number of scores you like using the 2020 Rules (Custom) selection by changing the following settings:
All other settings should be left as the default value, so be sure to check your current values against the default to make sure they are set properly.
In addition, you can set up a per-hole stroke limit when calculating handicap. See: https://www.golfleaguetracker.com/glthome/cms/help/how-to/strokes-per-hole-limit
Some leagues decide to calculate their handicap against par of the course rather than the course difficulty. Using the course difficulty allows you to adjust your handicaps based on the tee box and/or course that you're playing.
However, you can still set it up against par if so desired:
I also recommend the following settings: