Yes, you can become a millionaire overnight, but the truth is, if you invested a billion and lost everything. Joke of course. But still overnight to become a millionaire without having some initial large capital while for cryptocurrency it is more on the verge of fantasy.
I have a couple of examples of how people have become richer thanks to the purchase of certain coins. But they risked their money buying them. They risked tens of thousands of dollars, but received only about hundreds of thousands . Of any millions of speech can not be.