Keyboard.h doesn't work on Arduino Pretzel.

Keyboard.h doesnt work on my Arduino Pretzel from Franzis Internet of things.
Is the any alternative to Keyboard.h or another solution?

or another solution?

Use an Arduino board that the library is designed to work with

From the reference page for the library

The keyboard functions enable 32u4 or SAMD micro based boards to send keystrokes to an attached computer through their micro’s native USB port.