Making a grid and reading through it

Basicly, I'm trying to make a modified version of tetris as a practice to improve my sloppy programming skills. But I'm trying to figure out the basic logic and I came up with GRIDS.

This is a code to test my Block Type which would be all the blocks in the game. It's a prototype...

Const Cell_Size:Int=12
Graphics 800,600

Global Test1:TBlock=New TBlock
Test1.Create(10,10,0)

Repeat


Test1.Update()
Test1.Draw()
Flip; Cls

Until KeyHit(KEY_ESCAPE)
End

Type TBlock
	Field XCell:Int
	Field YCell:Int

	Field Category:Int
	Field Rotation:Int
	
	Field HCell:Int=4
	Field VCell:Int=4
	Field UCell:Int[HCell,VCell]
	
	Method Create(xstart,ystart,catstart)
		XCell=xstart
		YCell=ystart
		Category=catstart
		
		Select Category
			Case 0
				' Normal L
				UCell[1,2]=1
				UCell[2,2]=1
				UCell[3,2]=1
				UCell[3,1]=1
			Case 1
				' Line |
				
			Case 2
			
			
		End Select
	End Method
	
	Method Update()
		
	End Method
	
	Method Draw()
		For Local i:Int = 0 To VCell
			For Local i2:Int = 0 To HCell
				If UCell[i,i2]=1 Then
					DrawRect XCell, YCell, Cell_Size, Cell_Size
				EndIf
			Next
		Next
	End Method
End Type

EDITED

So basicly
4x4
[0][0][0][0]
[0][0][0][0]
[0][0][0][0]
[0][0][0][0]

0 doesn draw
1 draws on of the figure's cube

So let's say an L
[0][0][0][1]
[1][1][1][1]
[0][0][0][0]
[0][0][0][0]