Your best bet is to simply use opengl. (opengl can be configured to run from a terminal and even without any x renderer.)
Excellen! Let's opengl...
What do I need to write into this program to see the circle as well?
{$mode objfpc}{$h+}
program demo;
uses classes, sysutils,
FPImage, FPCanvas, FPImgCanv;
var canvas : TFPcustomCanvas;
image : TFPCustomImage;
begin
image := TFPMemoryImage.Create (100,100);
Canvas := TFPImageCanvas.Create (image);
{ Draw a circle }
canvas.Ellipse (10,10, 90,90);
{ Clean up! }
Canvas.Free;
image.Free;
end.