If I was you I would take it to a computer specialist to change any form of laptop parts and such; I have only ever done around 5 laptops and they are significantly more difficult than a desktop computer.
Some laptops have the videocard soldered/built-in to the motherboard, so you can't replace a videocard.
More expensive laptops have video cards which can be replace, but it is best for you to hire someone to replace the card for you since laptops are more hard to open and upgrade compared to a desktop.