As the Esri documentation states: Download, install, and authorize—ArcGIS Pro | Documentation
Install
ArcGIS Pro can be installed as a per-machine installation or as a per-user installation. A per-machine installation allows all users on the machine to use ArcGIS Pro. A per-user installation allows only the installer to use ArcGIS Pro.
Assuming you are not doing a silent/unattended installation, the installer will ask whether you want to install Pro for the current user or all users. If you choose all users, then you will get prompted for elevated credentials to install it. If you can't get elevated credentials, then it will default to install to current user. For nearly all 64-bit Windows programs, all users defaults to C:\Program Files and current user defaults to C:\Users\<username>\AppData\Local\Programs.
If the installer is suggesting C:\Users\<username>\Documents as the install location, something isn't right on the machine because installing a program into the documents folder is odd and likely problematic in the long run.
There are so many dots I can't yet connect on this thread, so I will just leave a couple parting thoughts/comments:
- ArcGIS Desktop/ArcMap and ArcGIS Pro licensing are completely independent of each other.
- ArcGIS Desktop/ArcMap and ArcGIS Pro are completely independent of each other from a software perspective, i.e., no part of one uses any part of the other even if both are installed.
- ArcGIS Pro supports Per-Machine (C:\Program Files) and Per-User (C:\Users\<username>\AppData\Local\Programs). Per-Machine installation requires elevated/admin permissions on the machine.
- Whether ArcGIS Desktop/ArcMap or ArcGIS Pro, none of the installation folders need to exist ahead of time, the installer will create the folders.