Guys I have done "Manage User Access" and the last session is Clone a user. I have done that assignment and got the exact results but it shows "Challenge not yet complete in Agentforce We can’t find a user named 'Kevin Park'.

Hello @Harshithaa Maroti

have you checked that the user has well been created behind the scenes, with the correct values ? Have you also cloned assignments as requested ? 

Test if your user has been created with Salesforce Inspector Reloasde or another tool : 

SELECT Id, Username FROM User WHERE FirstName = 'Kevin' and LastName = 'Park'

Eric