@Anonymous
Welcome to the Autodesk User's Community..
AutoCAD for MAC 2015 doesn't support that OS.. You need AutoCAD for Mac 2017.2 (https://knowledge.autodesk.com/support/autocad-for-mac/downloads/caas/downloads/content/autocad-for-mac-2017-full-version.html) or the 2018 version. Since you're a student, just go back to here https://www.autodesk.com/education/free-software/autocad-for-mac, sign in and request the 2017 version (but use the installer that I linked earlier). Drawings created in 2013, 2014, 2015, 2016, and 2017 are all the same "DWG" version format and there's no need to migrate any files that you create.
Mark Lancaster
& Autodesk Services MarketPlace Provider
Autodesk Inventor Certified Professional & not an Autodesk Employee
Likes is much appreciated if the information I have shared is helpful to you and/or others
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