It seems your problem of sending data from one screen to another is resolved.
However you have come across a different problem, where DatePicker.SelectedDate is giving you result in (probably) UNIX timestamp rather than in a human readable date.
You can try two approaches:
1 - Convert UNIX timestamp into date
Set(UnixTimestamp, DatePicker.SelectedDate);
DateAdd(Date(1970, 1, 1), UnixTimestamp, TimeUnit.Seconds)
For reference, current UNIX timestamp (at the time of this comment) is around 1718825791 -- so if you are getting something close enough, then you can be confident that you are getting UNIX timestamp
2 - Format the result from DatePicker
Text(DatePicker.SelectedDate,"dd-mmm-yyyy")
If your original problem of reading values from one screen to other is resolved, you should accept a solution and close this thread. If your problem now is to read date from DatePicker, then you should start a separate thread.
Please click Accept as solution if my post helped you solve your issue. This will help others find it more readily. It also closes the item. If this post or my previous reply was useful in other ways, please consider giving it Thumbs Up.