Below are external resources about the movement and Hong Kong if you want to learn more. They include the timeline of the movement, how you can become a part of the movement, and key protests that shifted the course of the movement.
To learn more about what has happened in Hong Kong from 2018-2020, you can refer to the source below.
http://tl.hkrev.info/en/timeline
This CNN page highlights the main protests that have happened in Hong Kong as well as the latest news and events in Hong Kong.
https://www.cnn.com/specials/asia/hong-kong-protests-intl-hnk
If you want to join the movement, here is a source about what you can do to help Hong Kong in different countries.