With a text layer selected, apply the Typewriter+ preset.
Edit the keyframes to adjust the speed of the typewriting animation.
By default, Typewriter+ will animate in one character at a time. You can change this setting to animate the text based on words or lines.
The default Typewriter preset only hides/reveals characters. This means that text won’t be set properly (center and right aligned). It also means that other tools and presets that rely on sourceRectAtTime() won’t work, since the bounding box of the text never changes.
Make sure your expression engine is set to JavaScript.
File > Project Settings > Expression Engine > Expressions > JavaScript