looking for "form calculation widget."

I have a form that I'm using square on for payment.

I am looking to ramp up the charges to members over time for the subscriptions.

I am not seeing the "form calculation widget" that the form builder is saying I need to use.

does square not support this feature?

under payment settings it's called "variable price." this is the setting I'm trying to use, but I can't find the widget it tells me to use...

thanks

You can add the widget from the Elements tab:

Once added to the form, you can then map it to the Square payment field.