Track date variable across a page

Hi I'm creating a page that has a few charts that pull data from another table.

At the top of the page i have 2 buttons that allow the user to go back a month or forward a month in data that they're looking at and a text field that displays the current month that the user is looking at. The date gets stored as a page parameter and is updated when the buttons are clicked.

My issue is that there doesn't seem to be a way to set a default page parameter to the current date(or month-year) so the script fails to load as the parameter is not set in the url.

For context when I manually add a date to the url e.g. https://test.com/myprogress?date=09-sep-2023

then the zml script with the buttons and text works as expected.

Is there a way to set a default parameter for the date in a script or from the link to the page?

Suggestions on how to track the month and pull that information into a charts better than the way described above is welcome to.

Thanks in advance, sorry I'm new to zoho creator so the jargon might be a little off.