To install the Windows release, simply download the binary (or from our release page); and ensure it is within your PATH.
To add earthly.exe to your PATH environment variable:
Search and select: System (Control Panel)
Click the Advanced system settings link.
Click Environment Variables. In the "System Variables" section, select the PATH environment variable and click Edit.
If the PATH environment variable does not exist, click New.
In the Edit window, specify the value of the PATH environment variable, and Click OK.
Close and reopen any existing terminal windows, so they will pick up the new PATH.
If you are going to mostly be working from a WSL2 prompt in Windows, you might want to consider following the Linux instructions for installation. This will help prevent any cross-subsystem file transfers and keep your builds fast. Note that the "original" WSL is unsupported.