Tip: Don't start saying ( I want to start a hedge fund./I want to trade for a living) until you've more thoroughly discussed the basics. And, have progressed to a more intermediate level of trading discussions. At this level, you can be more thoroughly body slammed. It drives the natives crazy! Welcome to ET, btw.
Do you have the ability to do a Google search? If you think the advice is bogus, then research it yourself. YES, the 7 is a harder test.
You do realize that in order to get the 66, you must have a 7? The 66 is a combo test of the 65/63. Usually, the big brokers (Fidelity, Schwab, etc) will require the 66 to be passed once you have the 7. But in order to take the 7, you have to have a sponsoring broker. The Series 65, however, does not require a sponsoring broker, and with that test you can start your own advisory firm.