Kinda funny, just yesterday, my kid found a solution for the issues he was having with fallout 4, and it was switching to use a local account

fallout 4 , was opening in window mode only, and no matter what we did it refused to read the setting to open full screen, also the game was not saving anything

he kept searching online, until he found someone suggesting to use a local account, and bingo, it fixed everything

i am not sure exactly why , but it seem it has to do with your home directory going through onedrive if you use an ms account , and this messed up the game ability to read settings and save progress