I connected the database to the "CardView".
I made the changes in the "CardView" field.

How can I make changes saved in the database?

I will supplement the question.

How do I make the changes save through the "designer" or with the help of the code?

Hello, Rich,     

Note that most of the forum threads are reviewed by Telerik representatives and sometimes we address the questions asked by our customers in the forums as well. However, a post in the forum doesn't guarantee you a response from the Telerik support team. Moreover, threads are handled according to license and time of posting, so we suggest you use a support ticket, which would be handled before a forum thread. 

Storing the changes in a BindingSource back to the database is a geenral programming question. You can refer to the following threads which are quite useful on this topic:
https://social.msdn.microsoft.com/Forums/windows/en-US/779f97cf-0f09-4c5a-9cde-097a717179db/how-to-save-datagridview-changes-into-database?forum=winformsdatacontrols
https://msdn.microsoft.com/en-us/library/0f92s97z.aspx
https://msdn.microsoft.com/en-us/library/y2ad8t9c.aspx

I hope this information helps. 

Regards,
Dess
Progress Telerik