College Student looking to get a racing bike for daily hard cardio— which is more reliable / better for my usage

Are those your only options? When it comes to antique bikes like those, we really can’t judge them from pictures. You need to make sure the bearings are in good condition, that the wheels aren’t worn out, that the stem or seatpost isn’t stuck in the frame, and that there is no rust hiding inside the frame. You will have to make this decision on your own after in person inspection.