Add your iCloud account to Windows. Enter settings in the Windows Search box, located in the lower-left corner of the screen next to the Start button.

When the pop-out menu appears, select Settings: Trusted Microsoft Store app, found under the Best match heading.

The Windows Settings interface should now be displayed, overlaying your desktop. Click Accounts.

Select the Email & app accounts option, located under the Accounts header in the left menu pane.

Click Add an account, found in the Email, calendar and contacts section.

The Add an account dialog will now appear, containing a list of account types. Select the one labeled iCloud.

Enter your iCloud account credentials in the fields provided and click on the Sign in button once complete.

A confirmation message should appear, informing you that your account was set up successfully. Click on the Done button to exit the Add an account interface.

Enter mail in the Windows Search box, located in the lower-left corner of the screen next to the Start button.

When the pop-out menu appears, click Mail: Trusted Microsoft Store app, found under the Best match heading.

The Windows Mail app will now launch, with your new account configured to download both your iCloud email and your iCloud calendar.