>after that to use the result to get a value form on select statment.
>
>SELECT @MPQ = SELECT MPQ FROM @RESULT + 'PARM'

DECLARE @RESULT VARCHAR(100);
SET @RESULT=''

DECLARE @mpq int;
SET @mpq=0

DECLARE @TableName VARCHAR(40);
SET @TableName = 'parm'

SELECT @RESULT  = OBJECT_SCHEMA_NAME ( OBJECT_ID(@TableName ))
DECLARE @sql nvarchar(4000)
SET @sql = 'SELECT @Test = Mpq FROM '+@RESULT + '.'+@TableName

sp_executesql @sql, N'@Test int OUTPUT', @Test =@mpq
SELECT @MPQ

not tested

I see you have no WHERE in your clause, that means you could have unpredictable results if you have more than one record in that table.