Is there a way to get the date viewed of the case just like the lead's standard facility of read and unread.
I am using omni channel but cases can also be manually picked from the queue.
if you read the Case objects Soap Api documentation, there are 2 fields that might interest you:
you can validate with the following SOQL:
select id, LastViewedDate, LastReferencedDate, CaseNumber, Subject from Case
and this will return a date in the following format per case record: