I am a complete novice at processing and have been trying to place three rectangles on the screen for most of the day and seem to  be getting no where fast... any help would be gratefully appreciated.

1. //variables
   float ballX, ballY, xVel, yVel, ballDiam=30;
   
   //set up
   void setup() {
     //set up size of screen
     size(500, 500);
     //set the stroke weight
     strokeWeight(1);
   }
   
   //start drawing stuff
   void draw() {
     //background
     background(0);
     //if the mouse is pressed...
     if (mousePressed) {
   
       //set ball x,y position to the same as the mouse position
       ballX=mouseX;
       ballY=mouseY;
     }
     //otherwise
     else {
       //place it to wherever it is according to the last throw
       ballX += xVel;
       ballY += yVel;
     }
     // draw the ball:
     ellipse(ballX, ballY, ballDiam, ballDiam);
     // any edge of the window, reverse its X or Y velocity
     if ((ballX<ballDiam/2) || (ballX>width-ballDiam/2)) xVel = -xVel;
     if ((ballY<ballDiam/2) || (ballY>height-ballDiam/2)) yVel = -yVel;
   }
   
   //adding another draw function for the bricks
   void draw()
   {
     for(int i = bricklist.size () -1; i>0; i--)
     {
       Bricks singleBrick = (Bricks) bricklist.get(i);
       if (singleBrick.collide(ball.ballX, ball.ballY, ball.radiusBall)) {
         ball.yVel = ball.yVel * -1;
         bricklist.remove(i);
         println("hit");
       }
     }
    
     class Bricks
     {
       float h;
       float w;
       float x;
       float y;
       Bricks(float tempx, float tempy, float tempw, float temph)
       {
         h = temph;
         w = tempw;
         x = tempx;
         y = tempy;
       }
       void display()
       {
         noStroke();
         fill(255);
         rectMode(CENTER);
         rect(x, y, w, h);
       }
      
     }
   
   
   
     //when the mouse is released
     void mouseReleased() {
       //throw the ball and set its volicity
       xVel = mouseX-pmouseX;
       yVel = mouseY-pmouseY;
     }
   

What I am trying to achieve is that when the user throws the ball, they can break a brick, and they have three tries in which to do so.