Is there any way I can use .Changed event for a table value?
You can use metatables for this, but you probably shouldn’t. Metatables only have any value if you are trying to make a module or function in order to simplify inputs and outputs, especially if you are providing said module as a free resource for other people. What you should be doing within your own code is making a function to call whenever the table is changed. Anything you write you will have control over, and so if you are the one writing code to change the table, you can call a function from there and avoid metatables.
I used PropertyModule and it works nicely.