I used team viewer in the past, for trouble shooting. I had it all setup so I could join in one click. But then they updated team viewer and everyone need accounts etc, so the solution became part of the problem and I ditched it.

Nowadays, windows has "quick assist", which works flawlessly to help one windows user as another.

Seeing your elders, who used to be fine with desktop computing, slowly struggling more and more because UX "developers" are a fucking joke is infuriating.