If you want to choose an appropriate topic, you should definitely
-make sure that the topic is not too trivial or too complex -it should have an appropriate length for your essay (so that you've not exhausted it pages before you should be done)
-find something that you find interesting - it will make it easier for you to to work on it and finish it
-make sure that the research you needed is available to you (for example not behind a paywall)