Amend 2024 Tax Return with Excess Pre-Tax Deferral

I am trying to amend my 2024 tax return in which has been accepted and completed by the IRS.  I do not have a 1099-R form but, I need to record income for a Excess Pre-Tax Deferral amount.  I am not sure where to enter the amount.  I have been told "Other Income", Line 1 h.  I don't know where that is at for amending my completed return.