Welcome to Android Central! Do you know if your device has a Chinese keyboard installed? Go to the App Manager and see if there is anything that looks like a Chinese keyboard. You can also go to
Settings>Language & Input, and look at what keyboards are available.
If you don't see anything, you could install some keyboards from Google Play:
Google Pinyin Input
Google Zhuyin Input
There are many other keyboards made by 3rd party companies as well, if you search on Google Play for "Chinese keyboard."