One should manually save out each action set "folder" individually to an separate .atn action file using the menu on the upper right of the action panel window and make a backup of the files.
The Actions Palette.psp file can often be used to easily migrate the entire panel/palette or to possibly retrieve unsaved actions. This is by no means a replacement for saving each Action Set as an individual .atn file. The location of the Actions Palette.psp file can be found in locations similar to:
Mac:
/Users/username/Library/Preferences/Adobe Photoshop CC 2022 Settings/Actions Palette.psp
(Replace “username” with your user account name and also replace 2022 with your version name/number. The Windows appData or Mac Library directory may be hidden. You can search the web for how to make hidden folders visible for your OS if this is the case).
I created a script to open up three common folders where custom settings are stored, to aid in manually backing up this data, including actions: