You don't need to remove the screen physically; just use the Function key to switch over to the external.
If you do want to remove it to replace it with a working variety, you need a 2.5mm Pozidrive screwdriver, a needle and a bank card.
The needle is to spear the little rubber bungs on the front of the bezel that surreounds the screen. Pull those out and you can see the screws they hid.
Remove those screws and use the bank card to very gently separate the bezel from the lid. Start on a top corner because it makes it easier. When you can see the edges of the screen, you have more screws to remove to free it from the side brackets.
Finally ease the screen out but not very far forward because you might strain the delicate...