Nice choice for a first camera. The best advice anyone can give you on starting out in photography is to go out and shoot, shoot, shoot. Take a close look at the photos. Examine them for focus, lighting, image quality and finally composition. If you have not already done it, pick up a manual dedicated to your camera. Magic Lantern Guides are good, but there are other books that you can use to find out what each button is on the camera and what its function is. Until you become familiar with your camera and can use the basic controls (almost) instinctively, it becomes a potential block to getting that photo that you might miss. See if you can change memory cards (it used to be film) without looking at the camera.
Now, for lenses. You must look at the kind of photography that you will be doing. Obviously, if shooting sports, like basketball, you need a telephoto, and the faster, the better. Weddings, landscape, model, etc. will dictate their own requirements. Since you are on this site, you can probably get by with a basic zoom in the 28-70 range. Again, the faster the better (ie. f/2.8 over an f/4-5.6) . Allowing extra cost for Brand Name hardware, basically you get what you pay for. One thing I will suggest: with the trend toward full-frame sensors, I would try to stay away from 'digital only' lenses. When you upgrade, you want to be able to use your old lenses.
The next thing to consider is software. It is easy to get an image into your computer, but if you are going to get to the point where you will be supplying your customer with a print that they can hang on the wall (for years!), you will need a good editing program. Of course Adobe Photoshop is the defacto standard, but Photoshop Elements and several other programs will serve you well. As with your camera, practice, practice, practice. You will eventually become very familiar with the basic editing tools.
I guess that is enough for now. Here are a few other things to consider:
--Pick up a dedicated flash (SB600, 800, etc.) as soon as possible.
--Start looking at photo printers. Consider the archival quality of the prints.
--Start learning about light modifiers - reflectors, etc. and become familiar with off-camera lighting, plus umbrellas, diffusers, etc.
--Consider tripods & other support hardware.
--You will need a good padded camera bag to carry everything.
--Memory cards are cheap right now. Make sure you have extra, AND try to resist the urge to shoot everything in JPEG. Start early with RAW files.
--Talk to others. Many of the members of this site are very opinionated, BUT they represent years of experience and if you look, there is lots of good advice.
--Remember that todays camera will probably become your future backup, so take care of it & clean it regularly.
--If you have not taken any photo courses, pick up a couple books on the basics. Read them and learn, then go out and practice some more.
Well, I think my answer strayed a bit off your question, so I apologize for that.
I'll let you be in my dream
if I can be in yours