You'd need to create a wrapper class for the PGraphics... like so:

1. class myPGraphics {
2.   PGraphics pg;
   
3.  
   
4.   float x;
5.  
   
6.   myPGraphics() {
7.     pg = createGraphics(400, 400, JAVA2D);
   
8.   }
   
9. }

Thx Cal, anyway i already had a wrapper class

I'm slightly perplexed by your code... it isn't valid and will fail compilation... also, if you're reassigning x to be zero every time display() is called, then why must it be declared for the PGraphics?

Aside from my remarks about your code, let's go back to the original purpose of this:

i'm trying to highlight the word if i hover over it

The text is displayed inside the PGraphics... do you really need this variable to belong to the PGraphics? Do you really need the PGraphics in the first place? Could you clarify the end goal of this that you have in mind?

Sorry for the confusion cause,

"i did not put the whole code as it's too big."
Sometime, it is worth doing a simple, minimalistic sketch illustrating exactly your problem.
A simple setup(), a simple wrapper class handling your PGraphics, drawing it on the sketch, trying to test the mouse over.
It gives a solid foundation to give an answer that you can then adapt to your complex sketch.
Right now, we have to give generic, vague answers since we have nothing concrete to point at.

Indeed, your wrapper class should know its offset with regard to the top-left corner of the sketch, so it can subtract this offset from mouseX and mouseY.
So the part that draws the image must also update this offset (the position of the PGraphics drawing) in the class.

hehe, thx for the advice, here's a mini sketch i do

Well, I don't see a class there... But it can serves the purpose.
What I explained is simple:

1. PGraphics drawingArea;
2. int a=30;
3. int b=50;
4. int c=100;
5. int d=30;
6.  
7. int drawingOffsetX;
8. int drawingOffsetY;
9.  
10. public void setup(){
11.   size(300,300);
12.   drawingArea = createGraphics(width, height/2, P3D);
13.   drawingOffsetX = 0;
14.   drawingOffsetY = height / 2;
15. }
16.  
17. public void draw(){
18.   image(drawingArea, drawingOffsetX, drawingOffsetY);
19.  
20.   drawingArea.beginDraw();
21.   drawingArea.background(48,48,48);
22.   drawingArea.fill(255,255,255);
23.  
24.   if (mouseX > a + drawingOffsetX &&
25.       mouseX < a + drawingOffsetX + c &&
26.       mouseY > b + drawingOffsetY &&
27.       mouseY < b + drawingOffsetY + d) {
28.     drawingArea.fill(255,0,255);
29.   }
30.   drawingArea.textSize(30);
31.   drawingArea.text("abce",a,b,c,d);
32.   drawingArea.endDraw();
33. }

The drawingOffsetX and drawingOffsetY are provided from the main program (it is the place where the PGraphics is drawn) to the class wrapping the PGraphics (so it knows where it is).

Thanks PhiLho, now i understand.