you cannot patent an idea.
you can only patent a design.
you would have to come up with a working prototype or set of detailed drawings.
you cannot just say ''i think remote controlled frying pans are a great idea, i'll patent it''
you must design it a working one
you should also check that nothing similar is already on the market - too similar and you will be refused.
you would be surprised at how most ''original'' ideas turn out to have been thought of before many times.