How can I populate a table with a foreign key?
Basically is a syntax "misplacement":

INSERT INTO Entries VALUES (entry_id, subject_id, student_id)


Column names should be placed before VALUES clause or, if you supply values for all columns in the table, you can avoid to use it.

INSERT INTO Entries (entry_id, subject_id, student_id) VALUES 


Try it on this way:

INSERT INTO Entries VALUES (1,4,1,'date'), (2,8,2,'date'), ...