In a democratic country, keep the people happy, stay in power. Is that how China works?

Yes it is, here's a Harvard Ash Center study proving it:

https://news.harvard.edu/gazette/story/2020/07/long-term-survey-reveals-chinese-government-satisfaction/

https://ash.harvard.edu/files/ash/files/final_policy_brief_7.6.2020.pdf

The survey team found that compared to public opinion patterns in the U.S., in China there was very high satisfaction with the central government. In 2016, the last year the survey was conducted, 95.5 percent of respondents were either “relatively satisfied” or “highly satisfied” with Beijing. In contrast to these findings, Gallup reported in January of this year that their latest polling on U.S. citizen satisfaction with the American federal government revealed only 38 percent of respondents were satisfied with the federal government.

I could speak more on this but I will match your low effort and pause there.

I'd rather not read any more stupid comments from smug and uninformed liberals like you in my inbox, thanks for the favor.