Comparing columns of numbers in Excel

I’ve never used Excel before yesterday, but I have two sets of data that I transferred into one spreadsheet and I’m trying to compare values in one column with values in another(not row vs. row). For example:

Column A Column C
1 1
2 3
3 4
4 6
5 7
8

I’m trying to figure out what is in column C that is not in Column A(6,7,8)added entries and what is Column A that is not in Column C(2,5)deleted entries.

My spreadsheets have from 350 to 4000 entries.

I’m not sure if this is possible or if I have to take this over to the excel board, wherever that may be. TIA