Are you looking for something along those lines?
WITH cte as
(
SELECT DISTINCT cvid FROM [x_ApplyJob] a
WHERE EXISTS (SELECT 1 FROM [z_JobChecking] c WHERE c.JobCheckingID = a.JobNoticeID)
)
UPDATE cv
SET score = 10
FROM cte
INNER JOIN [dbo].[x_CV] cv on cte.cvid = cv.cvid