Hi, I once started taking a laptop apart. But I do not know now! I somehow do not get the case off!
What now?
There are tons of YouTube videos on the subject
What is your goal?
Are you quite sure that you have removed all screws on the edge (in the deep holes). If so, you should at least be able to remove the lid with a little force.
If it does not go off at one point, check this area again for screws.
The case is normally bolted several times, under the rubber feet are also often screws inside.
When all are out, you can slide a plastic card into the gap between the top and bottom lids. With this card you go along the edge until the plastic clips are open. Then you can just remove the plastic lid.
Btw if it is not absolutely necessary I would not do it. There's a risk that you will tear lines and then the laptop is over, especially if you have never done that before.