Perform SUM() Calc with Where Statement then Insert SUM() Into another SELECT Statement with different FILTERS

I'm trying to SUM 12 columns together with a specific WHERE Statement to filter the data so the numbers are correct, and then I have to try to inject the results of that SUM into my main table for the report.

Below is some code I am working with and testing (its still very rough and I am building it one step at a time), but I attempted to use CREATE VIEW in order to get my SUM Results and I attempted to get that into my main SELECT Statement for the report but it wasn't working correctly at all so I abandoned that and just commented out the Create View block. But hopefully this gives a good idea of my overall plan is in my head.

There are other columns I will likely have to calculate the same way, so I'm trying to figure out the best way I can chain this all together in a simple but effective way.

End goal is a report in SSRS to compile 401k info.

/*
GO
CREATE VIEW [TOTAL CONTRIBUTIONS] AS
SELECT SUM(MTDWAGES_1 + MTDWAGES_2 + MTDWAGES_3 + MTDWAGES_4 + MTDWAGES_5 + MTDWAGES_6 + MTDWAGES_7 + MTDWAGES_8 + MTDWAGES_9 + MTDWAGES_10 + MTDWAGES_11 + MTDWAGES_12) AS 'TOT CONTRI'
FROM [DB1].[dbo].[UPR30301]
WHERE PYRLRTYP LIKE '3' AND PAYROLCD LIKE '401K';
GO*/


SELECT A.EMPLOYID, LASTNAME, FRSTNAME, SOCSCNUM,BRTHDATE,STRTDATE,DEMPINAC AS 'Term Date', B.YEAR1,
FROM [DB1].[dbo].[UPR00100] A
INNER JOIN [DB1].[dbo].[UPR30301] B ON A.EMPLOYID = B.EMPLOYID
INNER JOIN [DB1].[dbo].[UPR30300] c ON A.EMPLOYID = C.EMPLOYID
--WHERE 
GROUP BY A.EMPLOYID, LASTNAME, FRSTNAME, SOCSCNUM, BRTHDATE, STRTDATE, DEMPINAC, B.YEAR1, B.PYRLRTYP, B.PAYROLCD

Your MTDWages data is unnormlized, but I'm guessing that you know that and are not in a position to change that. However, you can use a CROSS APPLY(SELECT VALUES ...) to make it look normalized after which you can use built-in aggregation functions.

Something like:

SELECT A.EMPLOYID, LASTNAME, FRSTNAME, SOCSCNUM, BRTHDATE,
       STRTDATE, DEMPINAC AS 'Term Date', B.YEAR1,
       SUM(W.MTDWAGES) AS [TOT CONTRI]
FROM [DB1].[dbo].[UPR00100] A
INNER JOIN [DB1].[dbo].[UPR30301] B ON A.EMPLOYID = B.EMPLOYID
INNER JOIN [DB1].[dbo].[UPR30300] c ON A.EMPLOYID = C.EMPLOYID
CROSS APPLY (
    VALUES
        (B.MTDWAGES_1), (B.MTDWAGES_2), (B.MTDWAGES_3), (B.MTDWAGES_4), 
        (B.MTDWAGES_5), (B.MTDWAGES_6), (B.MTDWAGES_7), (B.MTDWAGES_8), 
        (B.MTDWAGES_9), (B.MTDWAGES_10), (B.MTDWAGES_11), (B.MTDWAGES_12) 
) W(MTDWAGES)
--WHERE 
GROUP BY A.EMPLOYID, LASTNAME, FRSTNAME, SOCSCNUM, BRTHDATE, STRTDATE, DEMPINAC, B.YEAR1, B.PYRLRTYP, B.PAYROLCD

If needed, you can also add a key:

CROSS APPLY (
    VALUES
        (1, B.MTDWAGES_1), (2, B.MTDWAGES_2), (3, B.MTDWAGES_3), (4, B.MTDWAGES_4), 
        (5, B.MTDWAGES_5), (6, B.MTDWAGES_6), (7, B.MTDWAGES_7), (8, B.MTDWAGES_8), 
        (9, B.MTDWAGES_9), (10, B.MTDWAGES_10), (11, B.MTDWAGES_11), (12, B.MTDWAGES_12) 
) W(Month, MTDWAGES)