How to USB tether on a Samsung Galaxy Tab A?
You can enable usb tethering through adb shell. Root is needed in order to execute these commands:

After adb setup on your machine (if you haven't already setup adb, please see detailed instructions here: Download Minimal ADB and Fastboot Tool &amp; Setup guide, perform these commands:


  The following commands call
  ConnectivityManager.setUsbTethering(boolean enable) in Android 4:


adb shell su -c service call connectivity 34 i32 1 turns on USB tethering.

adb shell su -c service call connectivity 34 i32 0 turns off USB tethering. 

(For other Android versions replace 34 with the following setUsbTethering calling codes per Android version):

5.1.0: 30
6.0.1: 30
7.0.0: 33


Credits

Is it possible to USB tether an android device using adb through the terminal?