Not sure if I understand the question correctly but you probably could use an UPDATE statement. Something like the following
UPDATE TableName a
SET BatchBookId = '1018439 - 2018 Low Income State Resource'
WHERE (BatchBookId IS NULL OR BatchBookId = '')
AND EXISTS (SELECT 1
FROM Project P
WHERE TableName.JF = p.Column1)
You need to adjust the table and column names to the ones in your database schema.