"Hey, I've got this great idea for an invention. It'll make a ton of money. All I need to do is patent it."
No, it will not, not by itself. But, assuming you have a real, patentable invention—what that is, is worth a separate posting—then you have a good start. But you have a lot of work to do.
The first step is to build a prototype. It need not be neat looking, because you are not going to sell it. But you do need to make sure the invention works as your base idea predicted. Nature is a notorious trickster, and the best-trained, experienced engineer or scientist cannot predict exactly.
Now, step two, get some capital together—your own, and from friends and family. You need it for the next three steps. Step three: do "upstream" marketing. That does not mean try to sell the product. You don't even have a product. Make contact with people and companies who might have an interest later, when there is a perfected product. Engage writing pad, not mouth. (Get each contact to sign a non-disclosure agreement.) This is where you find out the reality about the potential product, and maybe some things that will help sell it. ("No way we would buy that in grey, but if you make it beige, hey, call us when you are ready to sell!") Spend more for this upstream than the next step, R&D, and you will make money.
Here is a recipe for failure: "I don't need that upstream stuff—this invention is dynamite and I know it will sell like hotcakes."
Ok, step four: if the upstream tells you that you do have a winner, start perfecting the invention into a product, what is formally called "R&D." At the same time, start talking with a patent attorney, because step five is start up the patent process.
Step six is to assemble a management team, including you, but also an experienced business manager, a marketing/advertising person, and a finance person. You will need all these to manufacture and market your product. And to raise the money to start your manufacture-and-market company.
On the other hand, if your plan is instead to license your invention, you still need some R&D, enough to make a polished prototype to show around.
These steps all take time and effort. The great inventors you have heard of—who invented the light bulb, movies, the "talking machine," TV, the cell phone, antibiotics, Google®—you name it, all put in the time and effort, and made a ton of money.