Using reading to help with grammar
When we read, we see grammar in every line, and we can actively witness how the grammar rules we have learnt function in real English.
First you need to investigate and understand the rules for the grammar aspect you are having difficulties with. Once you have done that, you can start reading. Read something you enjoy, but when you do so, identify the use of grammar you are focusing on, remember the rules and see how they are used effectively and naturally. This will help to consolidate your knowledge and better able you to implement the rules yourself when you speak and write.
There is a lesson in the English Advantage course to who you how to use reading to improve your use of articles.