Hi Sushanth,
Add an association between checkout and car entities and on the overview page select the parent entity (in your case checkout). In this way, you can display all the attributes of both entities.
Regards,
Arun
How are these two entities connected? If it is a one on one reference you could use a nested dataview over that reference. You could also use a datasource micro or nano flow to retrieve the right Cart object and use that as the return value. You can then show all the attributes of that object in that nested dataview.
Regards,
Ronald