The writing of academic essays has been going on seemingly forever. As a student you should understand that the various stages involved in writing an academic essay have pretty much remained unchanged again seemingly forever. You would be making a serious mistake to try and reinvent the wheel. Know what the important stages of writing an academic essay are and follow them religiously. And by all means make your actual writing as interesting and as relevant as possible as far as the structure is concerned; learn it and use it.
If you as the student are allowed to choose the topic, this is hugely to your advantage. This is like a free kick in a football match. Take full advantage of this situation. Choose a topic about which you are passionate. Help yourself by selecting a topic which you will find easy to write and be enthusiastic about. You want the task to be as enjoyable as possible and you want the writing to be as good as possible. That will happen if you choose the right topic. Think long and hard about the topic.