How to start designing?
How would you model it in other CAD software?
You might start by getting a simplified idea of what you want the finished product to look like. There are a number of ways to do this, including 2D views, or Photoshop, hand sketching, or you could quickly model something as a single part in 3D. Usually the first concept is done in a tool that you are comfortable with and can change/create concepts easily.
Then you might use your CAD program to create individual parts that define the design such as the motor cover, or the base, or the blades.
The details of how you work in Solid Edge to complete the design of the individual parts depends on your design, and what you are using this for. Are you creating a prop for a game or virtual world/rendering background? Are you creating a production-ready model complete with manufacturing detail drawings?
The best way to learn the software is to download the 45 day trial https://siemens.software.net/store?Action=Content&Locale=en_US&SiteID=siplm1&pbPage=se_home and get going with the provided tutorials. Once you've completed a few of those, you should be able to figure out how to do most aspects of the ceiling fan.
If you're interested in some specific details, like how to make one of the brakets that mounts the fan blade to the motor, that kind of thing is a little trickier, and might require some individualized help.
There is a forum for Solid Edge where you will probably get better an faster help than on Grabcad. Give this a try: http://community.plm.automation.siemens.com/t5/Solid-Edge-45-Day-Trial-Forum/bd-p/Solid-Edge-Trial-Forum
That forum is specifically for the 45 day user trial.
Best of luck!