What does the outline include?
A thesis you can argue, a section for each stage of that argument, the evidence each section needs, and a rough word count per part. It is a plan you can write from, not a list of topics, the difference is that every section states a claim rather than naming a subject.
What should you type into it?
The essay question exactly as it was set, plus the word count. The word count matters more than people expect: a 1,000-word essay and a 4,000-word essay on the same question need genuinely different structures, and the outline will reflect that.
Can it write the essay too?
It can write an introduction, a thesis statement and a conclusion, and there are separate tools for each. Whether you should hand in generated prose is between you and your institution, most now treat it as misconduct. Using an outline to structure your own argument sits on far safer ground, and produces better essays anyway.
Other tools students use
Create a Study Guide, Generate Exam Questions, Simplify Complex Text for dense source material, Summarize a Book, and Solve Math Problems. Academic email tools cover extension requests, absence notifications and messages to instructors.