To make it easier for us to distinguish an essay from other genres, let us highlight its main features.
The topic of the essay is quite narrow, touching on some problem, prompting reflection.
The author's position, which can be subjective, is obligatory.
Publicistic presentation. Writing should be "magazine" language, not overcomplicating the text with a-writer reviews. Vividness and emotionality of the presentation is welcome.
The problem outlined in the theme should be considered in as much detail as possible, from different angles. It is obligatory to give arguments.
The essay is a fairly brief genre, averaging 3-5 pages. Therefore, a detailed consideration of the issue here does not mean that it is necessary to "pour water" on the topic. Your thoughts should be brief, but succinct.
The essay has no clear structure. But for the text to look logically, it is necessary to observe the standard composition: the text begins with the beginning, then there is a number of opinions and arguments, arising from each other, fastened logical connection, in the end - a small general conclusion.