Dual Boot ended up in a big mess

I have My (F:) drive redone as it was before. I am now ready to install Zorin16 Pro on (C:) drive as dual boot with windows 10. Is it my understanding you do not use the choice dual boot use the something else choice?

Here is My Gigabyte AX370 dealing with I assume Secure Boot: Notice that the choices are Disabled, Enable, or Legacy Only. Which ones should I change and select? Is changing this a must or can I wait and do it after I get Zorin running to where I can dump windows? If this is changed does Drive 0 (C:) need to be changed from GPT to MBR?

>>Windows 10 Features
Allows you to select the operating system to be installed. (Default: Other OS)
>>CSM Support
Enables or disables UEFI CSM (Compatibility Support Module) to support a legacy PC boot process.
eEnabled Enables UEFI CSM. (Default)
eDisabled Disables UEFI CSM and supports UEFI BIOS boot process only.
This item is configurable only when Windows 10 Features is set to Windows 10 or Windows 10 WHQL.
>>LAN PXE Boot Option ROM
Allows you to select whether to enable the legacy option ROM for the LAN controller. (Default: Disabled)
This item is configurable only when CSM Support is set to Enabled.
>>Storage Boot Option Control
Allows you to select whether to enable the UEFI or legacy option ROM for the storage device controller.
eDisabled Disables option ROM.
eUEFI Only Enables UEFI option ROM only.
eLegacy Only Enables legacy option ROM only. (Default)
This item is configurable only when CSM Support is set to Enabled
>>Other PCI Device ROM Priority
Allows you to select whether to enable the UEFI or Legacy option ROM for the PCI device controller other than the LAN, storage device, and graphics controllers.
eDisabled Disables option ROM.
eUEFI Only Enables UEFI option ROM only. (Default)
eLegacy Only Enables legacy option ROM only.
This item is configurable only when CSM Support is set to Enabled.