In order to Test physical Android device using TestProject agent you need to enable USB-Debugging and few other settings.
To enable USB Debugging please make sure all the settings on the device are exactly like this:
Enable "Developer options".
This could be done by entering "Settings" -> "About Phone" -> repeatedly tapping the "Build number".
You should get a message that says your enabled developer options.
Inside "Developer options", enable:
"Stay Awake",
"USB debugging",
"Disable Permissions Monitoring" option if it's available.
Under "Select USB configuration" select "MTP" or "File transfer".
Scroll down and turn the animation off for: "Window animation scale", "Transition animation scale", "Animator duration scale".
When you plug the USB cable to your Android device, you will be asked 2 things:
Allow access to device data -> select "YES"
Allow USB debugging -> select "OK"
Some devices require extra permissions try to follow these guides if you encounter an issue.