Is it ok to begin an essay with a question?
Make sure the question is phrased in a way that doesn't imply uncertainty of the answer. Don't have a question act as a motif since it is not your thesis; rather, it will likely precede the thesis since it's presented in the intro.
The previous answer seemed enthusiastic which is great, but it's important to recognise that questions in essays can make the essay in question seem informal which can often lead to a negative influence on the mark. But of course it all depends on whoever is marking the essay. Some teachers prefer content over structure, and some prefer formality over effectiveness.
It certainly is OK to begin your essay - or your paragraph, or your introduction, or your conclusion! - with a question. Indeed, it is often preferred that an essay begins with a question. Your opening question tells your reader exactly what your essay is about.
Your next step might be to mention briefly, in one paragraph, the issues involved in your question. After that, go on to talk about each issue in a separate paragraph, examining each issue from as many perspectives as possible.
End your essay by answering your question, and give reasons to support your answer.
You will probably begin your essay knowing what the answer to your question will be. One technique used by many in writing an essay is to write the question and answer first, and then the paragraph outlining the issues. After that, the rest of your essay will fall into place much easier.