I live in upstate NY in a house that was built in 2000.

I want to replace the cheap single glass basement windows with some
nicer insulated windows of the same size. How are basement windows
normally set in? I am hoping that the windows are attached to pressure
treated lumber that is in the concrete. Could they just be set in the
concrete itself? I think they are wood frame. If that is the case,
should I install the new vinyle windows with concrete screws (those
blue ones) and silicone?

What is best practice in this situation?