As a student, you know how to read, of course. But you have already learned that dealing with literature requires different skills. It’s not just about understanding the words. You also need to understand the content. You may need to break down the results of your reading in a way that you can reuse them and apply what you have understood.
Learning requires targeted reading and the ability to work your way through content in a structured way so you remember it.
Writing also demands targeted processing of what you have read. When writing a text, you generally refer to other texts, and systematic analysis of scholarly literature is typically the start of your own writing in that you explore the status of the research on your chosen subject area and take that as the basis for developing a topic of your own. You should always start with your existing knowledge and what you are interested in discovering. To tap into what you have read through your own thoughts, you need to be able to draw connections between that and your existing knowledge. Ask questions about the text and absorb the answers for yourself.