Scenario case and test case template or outline?

Question

I'm newbie and currently practicing as QA in a company ,,The company is building web applications and desktop applications
I have to do a scenario test case for the first time to compare the web-based application with the desktop application, what i really need is the basics or a sample template for scenario test cases??

My web application is an insert window for a product, with an update, insert, delete buttons. i don't know anything about database test case

Also is there a differnce between Test cases and test scenarios ??
thanks in advance