Hi Aesthir,
Welcome to the club! Congrats on your decision to buy a dSLR and starting this journey of photography.
First and foremost, before you consider what lens, eg 28-70, you want to get, you have to know what sort of photographic genre you want to go into. Examples, landscape, portrait, macro, night photography, events, etc.
As you can see, I am not listing a complete list of different photographic genres. So, before you run, as babies go, we learn to walk. So I'd recommend you to get a kit lens, and Noctis has given a good recommendation, the 18-135mm lens, to go with the 550D camera body.
Recommendations like that should be weighed carefully by yourself, because you are the one with the money and the one using the camera. Recommend you go down to the showrooms (not shops), like for Canon, its at Vivocity on Level 2 behind the Golden Village entrance, next to Challenger.
Give yourself the benefit of touching and having a feel of the camera. I don't know about you or your hands ... yes hands. They will hold the camera. As such, if you have a big palm, the 550D may be too small for you and it will end up giving you a 'pain in the hand' syndrome. Yes, ergonomics ... just like when we buy our fly chair for your reading den, it has to be ergonimically comfortable for you.
Should Canon not be right for you, there are other brands of camera, like Nikon, Pentax, Sony, Fujifilm, Ricoh, Olympus, Panasonic and Samsung. But before I confuse you any further, go have a fitting of your new camera first before you buy.
When you have decided, do your research on where are the best cluster of shops to buy such a thing from. Yes, Sim Lim Square is full of electronics shop, and they are full of sharks too. Do a search in Clubsnap on reputable shops that you should visit, and those that you should avoid like the plague.
Until you have acquired your gear, your next step will be to acquire the knowledge to go with your new advanced technological wonder called digital (hopefully, SLR) camera. Dun buy things that you are not sure of, read the threads posted by previous newbies too, so you don't fall into the trap of being 'chapped like a carrot head' syndrome.
Wish you all the best on this journey, and don't forget to post your questions, and most importantly, your pictures to share with us.
Cheers mate!