How to Enable Usb Debugging in Android

USB Debugging option greyed out

Finally figured out the solution to the problem, with the help of this post.

When you connect your phone to your PC, using the USB cable, select the mode as PC Software.

Now you should be able to enable USB Debugging.

USB Debugging in Android Studio 3.1.3

The instructions you followed refers to the Android device, so the actions:

On the device, open the Settings app, select Developer options, and then enable USB debugging.

needs to be done on your phone, not on the Android Studio.
Indeed, if you don't see any Developer options in your settings, just tap Build number 7 times.

More info at:
https://developer.android.com/studio/debug/dev-options

Any way to go directly to the Enable Usb Debugging page in Android?

No, it is not possible I'm afraid.

Here is a list of all Settings that can be opened with an Intent, note that USB debugging is not among them.

The closest you can get is opening up development settings (as the 2nd half of your question asked) with ACTION_APPLICATION_DEVELOPMENT_SETTINGS (more info), which does the following:

Activity Action: Show settings to allow configuration of application development-related settings.

How to enable USB debugging in Android?

Toggle on "USB Debugging" in the "Developer Options" area of Settings.

If you do not see "Developer Options", go into "About device" in Settings and tap on the "Build number" entry seven times, which will unlock "Developer Options".

As documented on Android Developers: https://developer.android.com/training/basics/firstapp/running-app.html

Android Emulator Allow USB Debugging dialog close right after showing

I had the same issue. I tried to click "Allow" in time, but it was too fast on my PC. However, I noticed that after a cold boot this popup pops and doesn't hide for some time (may be due to load lag), so I managed to click it this way.

If someone still has this problem and the goal is to upload some file or apk, better upload it to google drive and download it by link in the emulator.