Prevent Future Dates as Start Date on Redwood Non-Worker Page

Summary:

We want to restrict users to provide future date as start date on Non-Worker redwood page and show error message if start date is not same as Sysdate.

In VBS, currently there is no option to default Proposed Start date field value. So, we want to write validate message if date is not Sysdate it should throw error. Can anyone please help how can we achieve this?

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Version (include the version you are using, if applicable): 25C

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