Common Application and Coalition Application: These applications have their own essay prompts that change annually. Check the Common App website or the Coalition App website for the most up-to-date essay prompts. Ohio State will then consider your essay from these applications. There's usually *one* main essay required.
Ohio State University Application: This application *may* have additional essay questions *specific to Ohio State*. These are typically shorter than the main Common App/Coalition App essay. Check the Ohio State application portal directly for any supplemental essay prompts, as these can change from year to year.
In short: You need to check the application portal you are using (Common App, Coalition App, or Ohio State's own application) for the current essay requirements. Looking only at previous years' prompts is unreliable as they change frequently.