Automated Monthly data generation in SQL - sql

Question

I'm fairly new in ASP.NET and MSSql and I came across a problem, I have a House Rent payment system where I want to automatically generate a certain reminder like Pay-Rent at the starting of every month where I already have the transaction of payment of rent and return of advanced money given to the land-lord by the tenant after the first day of the month
...currently my database shows this
EntryDate Transaction Advance Rent Paid Description Advanced
Return
2021-01-27 Rent Paid 0.00 2000.00 2k rent received 5000.00
2021-02-20 Rent Paid 0.00 9000.00 9000 rent paid 5000.00
2021-03-10 Rent Paid 0.00 100.00 100 rent paid 5000.00
2021-04-6 Rent Paid 0.00 99.00 99 amount paid 5000.00
2021-05-2 Advanced Money Returned 1000.00 0.00 1000 rent returned 5000.00
...what i want to do is this
EntryDate Transaction Rent Advance RentPaid Description Advanced
Return
2021-01-01 Please Pay your rent 5000 0 0 0 0
2021-01-27 Rent Paid 0 0.00 5000.00 5k rent received 5000.00
2021-02-01 Please Pay your rent 5000 0 0 0 0
2021-02-20 Rent Paid 0 0.00 5000.00 5k rent paid 5000.00
2021-03-01 Please Pay your rent 5000 0 0 0 0
2021-03-10 Rent Paid 0 0.00 5000.00 5k rent paid 5000.00
2021-04-01 Please Pay your rent 5000 0 0 0 0
2021-04-6 Rent Paid 0 0.00 5000.00 5k amount paid 5000.00
2021-05-01 Please Pay your rent 5000 0 0 0 0
2021-05-2 Advanced Money Returned 0 1000.00 5000.00 5k rent returned 5000.00
this line which i want is to be autogenerated at the beginning of each month
2021-01-01 Please Pay your rent 5000 0 0 0 0
and this is the code of my StoredProcedure
SELECT RR.EntryDate, (N'RentPaid') as TransactionName, 0 as AdvanceReturn, RR.AmountPaid as RentPaid, RR.Description,MemberStartAmount as Advanced
FROM tblRentReceive as RR WHERE UserId = #UserId
UNION ALL
SELECT OGF.EntryDate, (N'Advanced Money Returned') as TransactionName, AR.Amount as Amount, 0 as RentReceive, AR.Description,
#MemberStartAmount as Advanced
FROM tblAdvancedReturn as AR WHERE AR.UserId = #UserId and AR.TenantId=#TenantId
ORDER BY EntryDate ASC
END
END
Where do i need to add that automated monthly row without breaking my union between two tables

Answer 1

The pseudo code:
START
for each record in master-record
begin
get the %MONTH% and %YEAR% of the record
create new record with day:1, month=%MONTH%, and year=%YEAR%, Transaction='Please pay your rent', and etc.
add the record and calculate the balance
end
add final-record 'Advanced Money Record' with the calculated balance
END
If you got the idea, you can translate it to tsql-stored-proc.