1. Inside Windows 10, navigate to the start menu
2. Select the Settings Icon
3. Select Update & Security
4. Select the Recovery Tab from the left-hand menu
5. Select 'Restart Now' under the 'Advanced startup' section
6. On the screen 'Choose an option' select the option 'Use a Device'
7. Select the alternate device you want to boot from.
Upon selecting the device you want to boot from, the device will restart and load the files found on the selected boot device.