First, read books and materials. It's best to look at the information of foreign countries or Taiwan Province Province. After having a systematic understanding, read more information on the Internet.

The modern history of China is closely related to the present society, so many expressions and viewpoints in high school textbooks are not necessarily correct, and the publications published in Chinese mainland are also different from historical facts under the influence of ideology. If you want to really study, you should read materials and books with critical thoughts.