Grub question

[Aravisian]

If you are dual booting, then it must show so you can select what O.S. you are trying to boot into.

If you do not want the grub menu and want to remove Zorin OS 17, that is an option.

Deleting Win 11, reformatting partitions to ext4, and combining partitiona using GParted

Partition 3 is the safe one. You do not need to format it - Instead, select it, then click the (-) delete icon. Then, select the Zorin OS ext4 partition 7 and select Resize (From gear icon or from Right Click) and slide the slider over to reclaim the unclaimed space formerly occupied by Windows OS.