Store Procedure with Date Difference and DateTime Conversion

@Parameter int,
@ParameterDateName DateTime,
@ParameterDateName DateTime
SELECT FieldName,FieldName,DATEDIFF(day, FieldDateName, GETDATE()) as abc,FieldName from TableName where DATEDIFF(day, FieldDateName, GETDATE()) > @Parameter
  and
  FieldDateName>= convert(datetime, @ParameterDateName, 20)
  and  FieldDateName <=  convert(datetime, @ParameterDateName, 20) 
 
  ORDER BY Fieldname  desc