Congrats to your father!
You said..."We already have a large amount of animals in the house such as Snakes, Dogs, Cats, Guinea Pigs, Spiders but the only one in my room is my Legless Lizzard"....are these all yours?
You said.."I need to know what I need and about them befor I get it"...here are some sites that have good information about chameleons...
http://adcham.com/
http://www.chameleonnews.com/
http://www.uvguide.co.uk/skintests.htm#discussion
You will need a cage, UVB tube light (Repti-sun 5.0's come highly recommended)(the UVB cannot pass through glass or plastic), some branches for it to climb on, some foliage for it to hide in, something to mist it with, thermometers, insects to feed the chameleon, something to keep the insects in, phos.-free calcium, vitamins, if the chameleon gets no direct sunlight you will likely need a phos.-free calcium/D3 powder, a dripper (once the chameleon is 3 or so months old), and I'm sure I've missed a few things.
You asked..."What are they afraid of"...they are usually afraid of things that could be a predator or that they think could be a predator.
You asked..."How can I tell if they are scared"...their posture and color will likely tell you that they are afraid. Its hard to be more specific until I know what species you will be getting. They will hide or run away sometimes too.
You asked..."What lighting/Heating they need"...they all need UVB light (as I told you above). The ambient temperature and basking temperature will depend on the species.
You askde..."How loud My music has to be befor it scares them"...I can't tell you for sure...but music that is not loud doesn't seem to bother them. Some of the chameleons sense the vibrations and I don't know how loud it would have to be for them to be bothered by it if it did even bother them. They all have relatively poor hearing.
You said..."Btw I saw the baby ones and they are pretty cute"...yes, they are....but for your first time owning a chameleon I would look for one that is several months old at least.
Please don't rush into this...it doesn't take long for problems to develop if you don't keep them properly.