Essay questions can seem overwhelming at first glance, but there is a tried and tested approach that can really help you get a great mark.
Firstly, it will help to prepare beforehand. Gather together all the topics you have been learning and write a list of vocab associated with each topic that could come up in the exam. Next, make a list of some useful expressions of opinion and connecting phrases (including subjunctive phrases) and learn them.
When doing an essay question, you will usually have a choice between 2-3 questions. Make sure you read the questions carefully and choose the one you feel you could get the highest possible mark in. Then write out the vocab you have learned that is associated with that topic on a rough page, as well as any useful expressions. Then write out a short plan for your answer, outlining the introduction, main body, and conclusion. The introduction should outline what you will be talking about, while the conclusion should summarise what you have said. The main body is important - it's usually three paragraphs, each containing a key point. When you have done this, start writing, sticking to your points and adding in key vocab and expressions as you go along. By including these things your essay will come off as really confident and well-structured, and you will have a great chance of getting a high mark!