Hi Ramon!
Although Walt Disney World is one huge property the four theme parks are quite separate. You can see how these parks are laid out on the
Disney Map. Each park has their own entrance with ticket windows, Guest Relations, security, and admissions queues. Some of the parks are quite close to each other such as
Epcot and
Hollywood Studios. The
Magic Kingdom and the
Animal Kingdom parks are set more by themselves. Bus or boat transportation is offered complimentary to resort guests.
There are vast parking lots set up for each park so guests can opt to drive their own cars. They are located out by the front entrance of each park but since they are so large it is hard to know exactly where a guest might have to park on any given day. If you wish to pay for the new
Preferred Parking Option at each park you will find yourself at the closest lot possible to each entrance. Although the parks have tram transportation for the parking lots many guests enjoy being able to park close enough so they just have a short walk to and from their car. Once you pay for this option you can travel from one park to another in the same day for the $40 fee.
Hope this helps get things organized in your mind. The property maps really help to understand how large Walt Disney World is. For many years you could put the Disneyland Magic Kingdom park in the parking lot for the Walt Disney World Magic Kingdom!