This article assumes you have already installed, downloaded and configured AVD (Android Virtual Device) and all you want to do is run it from the command line.
Use the emulator command to start the emulator, as an alternative to running your project or starting it through the AVD Manager. Here's the ... Start the emulator · Command-line startup options · Get help about command-line...
Android Emulator usage: emulator [options] [-qemu args]. options: -sysdir <dir> search for system disk images in <dir>. -system <file> read initial system ...
Run one of the listed emulators with -avd flag: emulator -avd name-of-your-emulator where the emulator executable is under: ${ANDROID_SDK}/tools/emulator.
You can set emulator start parameters in an environment variable studio.emu.params; they will be added to the command line when AS starts the emulator.