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.
This CNN page highlights the main protests that have happened in Hong Kong as well as the latest news and events in Hong Kong.
If you want to join the movement, here is a source about what you can do to help Hong Kong in different countries.