IELTS reading is a fairly straightforward task since you just need to gather information from a given passage, however struggling at this is understandable because the excerpts given are usually very long, and since you need to read from a computer screen for a long period of time, may cause strain on the eyes.

My suggestion would be to get yourself used to reading longer passages from books if you aren’t used to that. If you are, then try to drill some reading questions from the available website such as British Council or IDP, as well as do timed questions to get an idea of how you want to manage your time in reading on the test day.