Why cant we do graphics in sololearn

Question

an error occurred when I used <graphics.h> as file not found.compilation terminated

Answer 1

SoloLearn compiler runs your code on its servers and sends you the result as plain text.
Since you'll never see the graphics anyway, they removed <graphics.h> from their copy of the compiler.
If you want to play with graphics, you'll need to use a compiler on a computer.