Problem:

You have a bunch of things wrong with the code...
Also, go to Edit > Auto Format to make it look neater.

To skip to the chase, the much better way to do something like this is to use PVector; a compound datatype that can store both the x and y location.

Also, why are you using OpenGL if you are drawing in two dimensions?

Revised Code:

1. //Create and initialize the array
2. PVector[] numbers = new PVector[4];
3. 
   
4. void setup() {
5.   size(screenWidth, screenHeight);
6.  
7.   //Initialize the variables in setup()
8.   numbers[0] = new PVector(100, 200);
9.   numbers[1] = new PVector(100, 205);
10.   numbers[2] = new PVector(100, 210);
11.   numbers[3] = new PVector(100, 215);
12. }
13. 
    
14. void draw() {
15.   background(255);
16.  
17.   translate(width/2, height/2);
18.  
19.   //Loop through the array
20.   for (int i = 0; i < numbers.length; i ++) {
21.     //Access x and y positions with [variable].x and [variable].y
22.     rect(numbers[i].x, numbers[i].y, 10, 20);
23.   }
24. }

Typically, OpenGL is used for 3D rendering... and it would require that you import it first, so I wasn't quite sure what you were doing. If you leave that argument to size() blank (as I have done), it will use the default renderer; Java2D, which, by far, looks the cleanest...

You're not leaving size() blank, just the third argument; as I have done in the code above.
Like so:

1. size(screenWidth, screenHeight);