I would be great if some one explain regarding pension journal entry?
You need to furnish more information. There is nothing in Manager called a “pension journal entry” nor any process using that terminology. What are you trying to do?
End of each month I need to post pension contributions journal for Employees and employers? I would be great full if you advice me
You will find how to do this in guides on payslip items https://www.manager.io/guides/9667