Using datatable Group by 2 columns and sort by 1 column

Help Studio
1

I have data of 3k records. i want to groupby say column A and B and sort by column C. and perform some tasks on each group.
Please guide me on the same

2

@shrganes
find starter help here:
GroupBy_2Cols_OrderGroupBy-1Col.xaml (10.1 KB)

3

My column 3 is a date time so i have given convert.todatetime()

but i am getting an error
Object cannot be cast from DBNull to other types

4

please show your data samples so we can help more specific
empty strings will fail within datetime parsing and it looks that some rows do miss valid Col3 values