Starting with Windows 10 build 21390, you can now select Windows Console Host (default) or Windows Terminal Preview v1.9.1445.0 or higher as the default terminal application (emulator).
This means that any command line application (ex: PowerShell, command prompt, etc…) will launch inside your selected terminal emulator by default.
If you select Windows Terminal Preview, then when you open any command line application (ex: PowerShell, command prompt, WSL, etc…), it will open inside Windows Terminal Preview by default.
If you select Windows Console Host, then when you open any command line application (ex: PowerShell, command prompt, etc…), it will open in its own PowerShell, command prompt, etc… window.
This tutorial will show you how to change the default terminal application to Windows Console Host or Windows Terminal Preview for your account in Windows 10.