ive tried to graph an x and y vector but all i get is something wrong i know computers dont use Cartesian graph instead an x and y way of putting things on the screen. what i like to know is how do i make so my program plugs in the right

x and y to form a graph graphing them correctly on the screen here is the code i have so far. also im new to computer programming and dont know how to give my program correct variables names so if you see a few naming mistakes dont worry i kno i cant name things properly so bear with thanks. heres the code

1. size(200,200);
   
   
   for(int x = 20; x <= 180; x += 20)
   {
   line(x,20,x ,180);
   }
   
   
   for(int x = 20; x <= 180; x += 20)
   {
   line(20,x,180,x);
   }
   
   float space = 20;
   float bottom = space + 80;
   
   //middle
   fill(255,0,0);
   ellipse(bottom,bottom,10,10);
   
   float incrementbyy = 20;
   float incrementbyx = 4;
   
   float frombottom = 80;
   
   //top
   fill(0,250,0);
   ellipse(bottom,bottom - frombottom,10,10);
   
   //bottom
   fill(0,250,0);
   ellipse(bottom,bottom + frombottom,10,10);
   
   //left side
   fill(0,250,0);
   ellipse(bottom - frombottom,bottom,10,10);
   
   //right side
   fill(0,250,0);
   ellipse(bottom + frombottom,bottom,10,10);
   
   float incrementbyy1 = 20;
   
   for(int i = 0; i <= 160; i += incrementbyy1)
   {
   fill(0,50,100);
   ellipse(bottom,bottom - frombottom + i ,5,5);
   }
   
   for(int i = 0; i <= 160; i += incrementbyy1)
   {
   fill(0,50,100);
   ellipse(bottom - frombottom + i,bottom ,5,5);
   }
   
   fill(0,0,255);
   ellipse(20,20,2,2);