so I have a god understanding in electronics.
That good wow.
A LCD screen needs to be constantly refreshed with the screen image. The Arduino can’t do that because of lack of memory. Therefore you have to have a controller that has access to a memory that matches the display resolution and give it the task of doing the refresh. This controller has access to a port where you can talk to it and ask it to do things like change pixels or even draw straight lines. So to use an arduino you need this controller, memory and LCD display.
The problem is that LCD screens have a very short life, in terms of how long a manufacturer is willing to make them. They want to maximize their revenue so when the bulk order for the latest tablet phone or whatever is over they stop making it and move on. That means there is little available for the small guy like you and me. And what is available is very expensive as you can see. There is also very little documentation with such systems and what there is is very poor.
Look through what Farnell has to offer but maybe eBay is a better bet. However, you have to do a lot of work yourself on this unless you get to one that someone else has cracked.