EXEC ('StoredProcedure @Keyword = ''' + @Key + '''')

exec('exec <your stored procedure goes here>; select @@RowCount')

exec(`
declare @t table (
   <columns go here>
);

insert into @t
    exec(''<your exec here>'');

select @rowcount
');

declare @sql nvarchar(max) = N'exec '+@YOURQUERY + '; set @RowCount = @@RowCount';

exec sp_executesql @sql, N'@RowCount int output', @RowCount = RowCount output;

CREATE PROC PawanXX
(
 @a INT
,@b INT OUTPUT
)
AS
BEGIN

SELECT TOP 2 * FROM X

SET @b = @@ROWCOUNT

RETURN @b

END
GO

DECLARE @RC int
 DECLARE @a int
 DECLARE @b int

EXECUTE @RC = [dbo].[PawanXX]
   @a
  ,@b OUTPUT

SELECT @RC