Adding date-picker to form and customise format

hey there
I’m trying to add datepicker to my form and have to change the format to dd/mm/yyyy and the starting date is always +7 days from today, tried to use jquery but it doesn’t work.

share link : just click on the cake to enter the product page with the form
https://preview.webflow.com/preview/orshpitz?utm_source=orshpitz&preview=9ecaceccacf86ad5204244e22d45c6d8

looking for help… thank you very much!