How to create detail view in smart collection?

I have created Smart Collection but I can’t create Detail View.
For instance, if user click on the raw or record it can be visible as a detail view.

I know that we have to write api in route file but I don’t know what should I return and what forest admin expect to create that detail view.

Please help me by providing this solution. Your response would be appreciated.

Here is my smart collection :

When I click on this record. It seems error.

My expected output is detail view:

Thanks in advance.