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I'm not sure what you mean by this. Are you asking where you can add True Type Fonts?

If you wish to use other fonts with the TTF tutorial, you can drop the TTF file into the "font" directory of the tutorial, update initFonts() in text.c to tell the code to load that TTF instead of the demo font, and then also update the "Hello World" text in initDemo() of demo.c

You will then be able to render the glyphs you desire. Ensure that the TTF file that you use supports whichever glyphs you desire; for example, Google has a TTF that support traditional Chinese:

https://fonts.google.com/noto/specimen/Noto+Sans+TC

Otherwise, the tutorials themselves are only available in English, I'm afraid.