Himmatsj,
Yes, the order the other user stated is correct. Don't let all the technical details of the various connectors scare you off. It's really easy. I literally had no build experience and was able to do it back when I did.
Just watch a couple videos 1st, get comfortable with what you need to do, and just be careful. Once again, my advice assumes you are pulling out a card with similar connections. If that is the case, it should be pretty easy.
I am not comfortable giving out technical advice, or step by step instructions, however. But I can say this, if you have no build experience, like I did at that time, it is not hard. Its about as close to "plug and play" as it comes. I would watch a few videos before doing it, at least, just so you know. Be careful about static electricity, and trying to force connections, all connections should require some, but not a lot, of force. If it doesn't appear to fit, take a step back and look at what you are doing.
In layman's terms, what the other poster is saying (basically), after turning off your computer, unplug all devices from your existing card on the back of your computer - essentially your monitor, unplug the power connections from your existing card, pull it out of your machine, put the new one in the same slot, and plug everything back in.
Before you do this, you need to make sure your new card is compatible with your motherboard, that you have enough power, and that it will fit in your case. I just googled your case, and it looks like you have a basic Dell computer. You may not be able to get this card to fit, or have enough power.
I'd verify that before you start pulling stuff apart. PC's are actually pretty easy to build, until something goes wrong.... then you need to have some technical know how to troubleshoot. Something I wouldn't feel comfortable giving out advice on.