let the tool decide for you, if you choose manually a partition format you will not be able to boot. The correct ordrer to do this is:
1) browse for OS image and load it in to rufus
2) choose gpt for uefi option
3) DON'T change the partition format, let the application decide.
Media creation tool is a weaker application, i would use rufus to do this, use the media tool to download the OS in ISO format then use rufus to make the bootable USB.