1. As an American, you can go to Cuba only if your visit falls under one of 12 government-approved categories.
So no, you still can't go to Cuba just to lounge on the beach, as vacation and leisure travel are still not allowed. But it's certainly a lot easier to go than it was before, when Americans had to get pre-approval from the U.S. Office of Foreign Assets Control to visit the country.
All you have to do is be sure that your visit falls under one of the*12 government-approved categories, such as family visits, journalism, professional research, and support for the Cuban people, to name a few.
Also, as of this month, Americans can now plan their own "people-to-people" trips, which basically means that you can now make your own schedule to spend time with Cuban people (whereas you had to do it through a group before). If you go on one of these trips, you are expected to have a full-time schedule of your activities.