Merge two boot partitions

I have Windows dual-boot with KDE Neon, and I can boot to each OS easily. But there are two boot partitions on my PC, though I set up for one when I install neon. I mount /boot into /dev/nvme0n1p1, and it contains both neon and the old windows (does not work) boot files. But when I boot into windows, it boots from /dev/sda2, which was created after troubleshooting boot options on windows. So can I merge them into one partition, /dev/nvme0n1p1?

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