Cannot use Nvidia card in Ubuntu 16.04

Hello I am trying to switch my GPU to GTX 1060 from Intel® HD Graphics (Coffeelake 3x8 GT2). I installed Nvidia driver and selected it active from “Additional Drivers”. After doing that I rebooted my PC but then I get “No discrete VGA device found.” Any solutions?

Please run as root and attach the resulting .gz file to your post. Hovering the mouse over an existing post of yours will reveal a paperclip icon.

When I “sudo” it says “sudo: command not found”.

Normally, it’s installed alongside the nvidia driver, did you uninstall it?

I did not uninstall it. And also I installed Nvidia driver with “sudo apt-get install nvidia-415”.

Maybe the paths are not properly set. Try
sudo /usr/lib/nvidia-415/bin/