If you really mean "large RAM (60KB or more)"! PICs don't have large RAMs. (8 bit parts) I have not used 16 and 32 bit parts.
If you need large data RAM then look at ARM computers.
If RAM can be slow look at an external serial RAM that almost any little PIC can use.
GLCD Image takes 60KB, however it refershes itself.
I was thinking that every time I'd like to display a certain image on the LCD, the laptop will send the PIC a 60KB image and the PIC will load it in the LCD.
So, therefore I was thinking that I'd need 60KB RAM for that.
You don't need 60kb of RAM. The PC needs 60kb RAM. The LCD has 60kB of RAM. The PIC only pass the data and does not store anything. The PIC is like the wire between the PC and the LCD. The wire and the PIC do not need to store anything.
And allow for the time to send the data, even at 115kbaud that's only about 11kbyte per second, so 60kbyte sized image will take over 5 seconds to transmit and display.
That could look pretty bad if it required to display one image after another.
If we knew what you want to do we could help.
If you only want to display text then you can hold the entire display in PIC RAM because only the ASCII is in RAM not the displayed graphics.
The MPLAB debugger can be used with MPLAB SIM or with the PIC itself. Some PICs have 1 while more modern ones have 3 breakpoints that can be used for debugging. When debugging with the PIC it is called ICD or In Circuit Debugging.