As you stumbled upon, Keyboard input in Duality comes in two flavors: Keys and chars. You probably guessed it, but mapping between the two is an incredibly complex endeavor that I would not recommend - it starts with control keys (Shift, Alt) but doesn't stop at handling different keyboard layouts (QWERTY, QWERTZ, etc.), as well as user-defined custom mappings in the operating system.
So instead, you'd in fact use DualityApp.Keyboard.CharInput
when you want to know what text a user types vs. which key they pressed. Every frame, the returned string contains the sequence of characters that was entered since last update. You can use it like this
and observe the code in action when you install the input handling sample package via Duality package manager.