There are numerous similar questions to yours in various threads on RP. I can only encourage you to explore the web site to seek out those other threads. BUT,... I will offer up my opinion concerning your questions:

Originally Posted by
clint802002
I think being a police officer could be something that I really enjoy, but since I have never done it, it is hard to be completely sure. I was wondering how yall knew this career was right for you.
Everyone is obviously different when it comes to "what" exactly inspired them to get into law enforcement. I can nly encourage people like yourself to seriously consider going on a ride-a-long with a local agency in your area. If you're not sure where to look for this program, try either your local PD's web site for more information or simply call the department and ask! If they have such a program in place, consider going out sometime with one of the officers to get a first hand look at what it's all about...

Originally Posted by
clint802002
Another thing I was wondering is how hard is it to get into different departments.
Short answer: Depends on the department. Departments commonly have different regualtions, standards and policies. Best approach is probably contacting each department's recruiter you have an interest in to find out first hadn what they each require. There is no universal standard all departments abide by.

Originally Posted by
clint802002
I would like to go to Homocide, Swat, or there are many others that interest me. It seems like a lot of police officers stay patrol officers though out their careers, is this by choice or is it just really hard to get into other areas.
Commonly, at most departments, everyone starts in uniformed patrol, serving a couple of years at least in most cases, before going into specialized areas such as SWAT, Homicide, etc. How "hard" is it to enter those special divisions? Again, depends on the department and what kind of selection criteria they have to move someone into those areas.
A lot of officers do stay in patrol for a number of reasons. Some don't want to specialize. And a patrol officer's position should NOT be regarded as anything less! Patrol personnel are the "backbone" in any department...
--
Charlie
"Good and evil are present in this world, and between the two there can be no compromise" - President George W. Bush, in his farewell address to the nation.