What's the difference between suggestion and idea

An idea is a thought , notion or a concept as a result of mental activity - mostly individual but can be by a group also.

Suggestion is process of inducing an idea in a receptive person without using persuasion or coercion.

got it from quora.com

suggestion is an act to ask a or some suggestion to other people, like needing help, and ask someone.
Idea is a way to imagine what we think