I just installed ArcGis 10.7.1 and activated the student license. I can open ArcCatalog but not Arcmap which shortly after starting shows me the message: '' ArcGis has stopped working: please wait while we gather information about the error ... '' I uninstalled and reinstalled it but nothing changes.
Have you tried the steps in the Esri KB about ArcMap not opening? It is fairly common for corrupted templates or profile caches to cause problems with ArcMap opening.