- On the 'Installation Type' menu, select 'Erase disk and install Ubuntu' (don't worry, we will select dual boot in a subsequent step).
- Next, click the 'Advanced features...' button.
- Select 'Use LVM with the new Ubuntu installation' and check 'Encrypt the new Ubuntu installation for security'.
- Click OK. Return to the main setup screen and select the first option: "Install Ubuntu alongside Windows Boot Manager".
- Proceed with the installation to configure your encrypted dual-boot system.
Watch this video tutorial for a visual walkthrough:
Guide: Install Ubuntu with LUKS encryption alongside Windows