Android Studio does not display the emulator that is on the pc nor by the usb device in the mobile phone how to fix this. follows an image to help, as you can see no devices appear.
Regarding the physical device: Is your phone in Debug mode enabled? If it is not, it will not appear at all. To enable debug you must first enable the programmer mode on the phone. For this you can follow the guidelines of this link: link After that, enter the programmer option that appeared in the settings and enable "USB Debugging".
If everything is okay on the device, the drivers are probably missing on your machine so that it recognizes the phone. You can find the procedures for this at this link: link
Regarding the virtual device: Make sure you have created it correctly in AVD Manager, including whether the Android version of the device is compatible with the minimum version of the SDK you have chosen.