How to use multiple languages in a project

Hello,
I am engaged in the translation of the game and met with such a problem that my font does not support the Chinese language, and how and where to make sure that when choosing the Chinese language, a different font is selected for all fields and widgets?

You can create an alternative assets for each languaje you need. In the case of fonts, take a look at this image, where you can select witch one need to be selected taking in consideration you languaje:

Just use the composite font, inside you can select English font and Chinese font, it works for me, i use English, French and Chinese