How do I find the path to a partition in my device when connected to my computer with adb?

$ adb shell df -h

This command lists all mounted block devices

On the shell you can use the command

    
adb shell mount

  

to see all mounted filesystems. This inclused the filesystems of your work profile. It could be required to run adb as root, then you need to enter

    
adb root


  

first

Not exactly sure what you're asking for but

        cat /proc/mounts


  

will reveal all mount points on the device aswell as which device is mounted there.

If you know the name of the partition, you can access it in /dev/block/by-name, or find out where they point to by using ls -lah /dev/block/by-name

But not really sure what you're asking

If you want to copy a partition, you're going to need to have root access.