Re: 32 Gigs
I know the feeling well ! I bought a secondhand Asus and also discovered that it was similarly un-upgradeable due to a crappy 32GB storage inside it.
I got around this problem by "force-feeding" the very latest Win 10 - deleting anything that stood in the way - with perversion Win 10 May 2019 issue.
I then shifted it to someone else just to get rid of it.