Thank you again, dumi!
one question: If I write a hook, will it help me get a higher score in IELTS?
Of course, a good hook will definitely help you with impressing your examiner and that fact alone helps you earning good marks for this task .... LOL
However, if you do not get a hook at once when you start writing, start with the background which is easy (only you have to paraphrase the topic ).... So, once you get into writing, you would get some idea to insert as a hook a little later :D That's a tip!
However, in my view, even if you don't have a hook, it may not be a very very serious issue.