Did something similar with my aunt. She bought this laptop that had Windows 10 installed on a hard disk. Right click the Start menu to open the Properties dialog, go make a sandwich, you’ll have half the sandwich eaten before the right click menu opens.
I added a SATA SSD and a stick of RAM, and a copy of Mint Cinnamon. She took right to it, especially when I showed her how the software manager worked and that it’s very similar to the Play Store on her Samsung tablet.
Reminded her a lot of the WinXP and Win7 desktops she used to have.