@cardsfan27 - The first thing anyone needs to do when they believe they have invented something, or may have made a discovery, is to immediately file a patent claim with the United States Patent Office.
If someone files a claim right away it does not matter if someone else comes in claiming credit to the same invention, because the date of the claim is all that matters.
I heard a story that Alexander Graham Bell, who invented the telephone, filed his claim a mere few hours before another person claiming the invention.
Also, a person should always follow up with the patent office, as it may take a couple years for them to research and make sure that it is in fact a new discovery.
As far as being a full time inventor goes it all depends on the ideas one comes up with and whether or not it is something marketable and that they will be able to make a living off of it.
Besides that, one only needs to follow procedures in the patent office and anyone can become an inventor.