Your first paragraph is a very common and overused way of starting an admissions essay. Try to change it.
I'm not saying that you cannot say all those things about your childhood. However, you should include them in a way that is different from others. Read some other essays and you'll understand what I mean.
You can start with a short description of an experience from present and then connect it to one from your past. This is just an example.
Unlike most, a moderate understanding is not enough for me.
I don't like this sentence. It makes you seem a bit...bloated...you know what I mean??
The third paragraph is not good. Here you've put things which everyone knows. Are they really the reasons you want to pursue comp sc.? Do some research into the new and upcoming fields of computer science. You'll see that you will have more than enough material to talk about.