I am new to this calculator what do I have to do to download zip files from this site and get them to my ti 84 plus c silver edition any help is appreciated

You need to go to the archives section, select the subfolder /84pcse, and from there, move through the submenus to find whatever program you want. Once you find it, click on the name of the program (in red) and it will download. Once downloaded, you simply need to unzip it and follow the instructions in the included instructions file (all files uploaded to the archives require an instructions file). Usually, this will simply be to send a .8xp file to your calculator, but some programs may require things like hybrid basic libraries, appvars or subprograms to run correctly. If they require hybrid libraries, then you will most likely have to download and install DoorsCSE. If they require any appvars or subprograms, then you will need to simply send those as well.
To send files to your calculator, you will need to have a linking program. I usually use ti-connect CE, which can be found here, but you can use any one you like.
In ti-connect CE, all you have to do is plug in your calculator, open up ti-connect CE, move to the "calculator explorer" section, and drag in the files you want to send to your calculator, then click send in the window that pops up. Other linking programs like tilp and ti-connect (the old one) will be different. Once you've got the files on your calculator, all you need to do is run them. If you've gotten the program from the \asm subfolder, then you need to run the program like this:

Code:

If you got it in the ti-basic section, then you don't need the Asm( token, so it is just
Code:

If what you've downloaded is an application (.8xk), then you will need to go select it from the apps menu.
There is probably a more extensive tutorial somewhere, but this is the basics of how to send something to a ti-84 PCSE.