
Shall I delete the partition and add it to NTFS partition?

Shall I delete the partition and add it to NTFS partition?
I wouldn't delete it. Installing Ubuntu normally creates two partitions, one big one and then a small one. Most of Ubuntu is on the big one, but some of the instructions that the computer follows in order to be able to read the big one might be in the small one.
And now, for the longer explanation of what I think that partition is (trying to make it understandable, but I'm not sure what you and other readers know or don't know in advance, so I hope this is clear and isn't dumbing down )
I don't think the UEFI (the code that runs when you turn on the computer and figures out what should run next and reads that from a disk and runs it) knows how to read ext4 or NTFS, so some code is stored on a FAT32 partition, and that code contains the instructions on how to read the other partitions.
That is, I'm guessing it's the "EFI boot partition": ''EFI boot partition'' and ''biosgrub'' partition
I don't know how much of Ubuntu is stored on the small one. But at least some part of GRUB (the programme that shows a menu so you can choose when to boot Windows and when to boot Ubuntu) would have to be on a FAT partition.
In general, I wouldn't delete stuff without at least having some clue what it is and where it might have come from.