Hey there, thanks for starting this thread. I recently switched back to Windows 10 after using a Mac for several years, and I ran into the same issue when installing InDesign 2021. It ended up getting installed in my user folder instead of the programs folder, just like you experienced.
I did some research and found some helpful tips on Windows 10 product key Reddit, where other users were also discussing this issue. One suggestion was to try installing the program as an administrator, which could help it install in the correct location.
Another suggestion was to manually move the InDesign 2021 folder from the user folder to the programs folder. However, this method can be risky, as it may cause some files to become inaccessible or even corrupt.