Ideally, that is kind of the point of Wikipedia, so it may not be for you. Blatant promotion, propaganda, and personal benefits have a pretty good chance of getting edited and/or cut pretty quickly.
It is a good place to pick a topic and use that as the basis for honing skills in writing, thought organization, research, source documentation - all of which could serve you well outside of Wikipedia - even if helping others through sheer chance.
It is an evolving project. I am not involved with it, but use it is as a source. Independent verification of facts is important more than ever - and harder to provide due to the volume of data and repeated data in the world that is not valid.
Selecting a single topic and developing to a high standard should pay off in your everyday work.