I am still a noob at this

Solution
Nope, on a laptop your graphics card is integrated into the motherboard, and the motherboard for your laptop is not upgradable or replaceable.

so does that means that i need to buy a new one ?

 


Yup on laptops if you want to upgrade you pretty much have to buy a new one.
 

So i was thinking of buying this
ASUS K55N-DS81
since my budget is around 500 dollars. Is it worth the shot ?
 


Sure Asus is one of the better laptop manufacturers on the market from what I've heard.