IF NOW with Date and Data

[Snowman1977]

I take attendance using a scanner device and an excel spreadsheet. I also have a gradebook in excel. I'm trying to do an IF THEN (NOW) type of scenario. For instance, if ZOE is in attendance on 3/8/2021, I want the gradebook to record an "X" for a student named Zoe because she was present. If she were not listed on that specific date, then it would put an "A" for absent. This is between two sheets in the same excel file. Can anyone help me with the correct IF arguments because I'm having difficulty getting this right. 

[#2]

@Snowman1977 The TODAY function might be a better function to use. Can you share the workbook, removing any sensitive data, to get a better idea of the data and how the two worksheets are related and differ from one another?

[#3]

It would be reasonable to assume to reason that if they do not sign in they are absent so why would you need to record X is for absent