Hi Aman,
I doubt this way you are doing the insertion, you are iterating the same excel list 4 times.
Iterate only once and do the insertion.
How: For example If your excel is giving you RoleName and in the employee table you have to insert the RoleId then create one server action which accepts the role name, filter the record based on role name and return the roleId, call this server action while iterating the list and assign this returned roleId to Employee.RollName variable.
If you wanted to do the same way you are doing at present then do something like this to resolve your issue :
I created two server actions :
GetEmployeeByName - Based on the Input name it will return EmployeeId
GetExpertiseByLabel - based on the input expertise name it will return the ExpertiseId