Basically I have a database added to my project, and I need to know how to make a column map to another table.

I have attached a couple of screenshots to show you what I mean, I want the "Absences" to be a new table, instead of a single DateTime.

So create a new table, and inside of it create some columns: AbsenceID, StudentFK, Date.
This means each row will have its only id (primary key), foreign key to the Students table, and an actual absendce date.
So you will have this kind of structure:

Student: StudentID, Name, Age,... (and no Absence)
Absence: AbsenceID, StudentFK, AbsenceDate