how can I connect the database, synchronized live, to order the repeaters according to the distance of the visiting user.
Hey
This is not that easy and if you do not code yourself I would suggest to head over to Wix Arena to hire someone to help you. You can always get help from me at wixshow.com under Get Help!
First of all you will need to store address information per item in your Data Collection or even better and faster the longitude and latitude information of every item.
Then you need to use wixWindow in Wix Code to get the geographical information from the user.
Then you will need to code in Javascript to calculate the distance between the longitude and latitude from the user to each and every record in your Data Collection.
When this calculation has been done per record / item you take that result as an array and populate the repeater with the new data, Distance and hook that information up to a text field just as your design shows.
You cannot use document.getElementById inside Code Panel in Wix Code.
To calculate distance in Javascript you have an example here.