Take a tour that shows you Miami Beach and Star Island. I recommend a company called Thriller as they provide quick, interactive and action-packed speedboat tours! These tours combine the perfect amount of information with fun, leaving you more informed, with great memories, and with a ton of time left in the day to do as you please!
One of the biggest drivers of the economy in Miami is tourism. You can go out any night of the week on Ocean Drive. There is always something going on there because there are always tourists (more in high season). Other cool neighborhoods to check out for a less touristy experience are Brickell and Wynwood. Brickell tends to be more latin-oriented while Wynwood has more of a hipster vibe to it.
The city has a heavy Cuban influence. Little Havana is where you can find Cuban Cigars and Cuban Coffees - the former I have heard to be great and the latter I personally know to be great! Miami has seen a recent influx of many Venezuelans as well, predominantly because of the current situation in Venezuela.
Miami is expensive, wages are not extremely high, there are not a ton of jobs, the city can get very humid, and hurricane season will make you nervous. If you can survive the aforementioned drawbacks, can speak some Spanish (Portuguese is helpful to know too), enjoy hot weather and beautiful beaches, and aren't opposed to frequent partying, then Miami may be the place for you!