I\'m installing Imagemagick on AWS Lambda and it appears that the fonts that Imagemagick normally uses aren\'t preinstalled, how can I add additional fonts?
You can't.
The reason you can even use Imagemagick with your lambda is because AWS Lambda team had pre-installed this library on their containers.
This is true for Lambda's running on NodeJS - which has libraries for operating the Imagemagick installed on your OS but not running it itself.
You should examine using C# / Java runtimes - which might have the Imagemagick library that you can add to your Lambda (not sure about that).