If the Secure Boot Control function is not present in the BIOS, then you can only get rid of the (error) message by converting the diskformat to MBR.
You will have to format the HDD/SSD, so all the data will be wiped
Why would I want to downgrade my hardware in order to upgrade my software? That makes no sense. No thanks, I'm not going to break my system to get rid of a Microsoft generated error - they need to fix it, not me.