Loop through all .xlsx files in directory and copy data in those files into a new file

I have a bunch of .xlsx files in a directory called 'testing'. I would like to create a macro to do the following and copy the results into another file named 'Results' in another directory called 'check':

- Open each .xlsx that exist in directory 'testing' and run a macro to do the following:
1. Copy cell A2 into column A in file 'Results'
2. Copy all cells that contain data in Column C into column B in file 'Results'. Remove duplicates and only keep unique data.
3. Close file

Attached are sample files TP1 and TP2 that are in 'testing' directory. File 'Results' contains what I would like the output to look like.

I would appreciate any help on this. thank you so much.