Write the following command in your terminal:
adb install [-rtsdg] <file>
Note that you have to pass a file that is on your computer and not on your device.
If you append
-r at the end, then any existing conflicting apks will be overwritten. Otherwise, the command will quit with an error.
-g will immediately grant all runtime permissions.
-d allows version code downgrade (only appliable on debuggable packages).
-s to install the application on the external SD card.
-t will allow to use test applications.