Q&A: Important to Read Online
Answer: Not reading.
That might sound odd, because all college classes require reading, sometimes a lot of reading. Teachers have been complaining about their students not reading for centuries. Still, it is even more important online, because there are fewer options for gathering information.
In the traditional classroom, you might focus on the instructor's (spoken) lecture, take notes and prepare for the test. In a discussion-based class, a classmate's comment might bring something into sharper focus for you. Teachers have a well-meant but dangerous habit of explaining assignments out loud and directing your attention to key points, so you don't have to learn to analyze assignments on your own.
In other words, in a traditional classroom there are circumstances where you might skip the reading and still be fine. There are no such circumstances online.
Some schools offer audio versions of texts or lectures in movie format. But overwhelmingly, the common way to give instruction is via written text. This includes key points like school-wide policies. Policies governing things like submitting late work, or whether you can re-use assignments from one class to another differ radically from one school to the next, and even one class to the next. If you don't read those policies, you might submit first rate work and get an "F."
On the most basic level of learning, when a class is text-based, you have to be willing to read, if you want to learn. Ideally, you would be willing to read and reread the works, analyze them, reread the lectures repeatedly, take notes and convert those to formats that help you remember and apply them. All that would be great, and your teachers would love you for it…but plain old reading is the foundation.