How do you code a object counter in Mit App Inventor?

I would like to figure out how to number how many textboxes I have like 10/10. Then I would like for that number to go down every time the textbox goes away.

what does that mean?

Is this what you were looking for?

And, the same way, you can manage to count number of textbox(s) do you have at run time, using any component. If, that's is your concern.