Otherwise, for other reading people that are inexperienced as I am, this worked for me, as Renate said, nothing else was needed except writing the boot image:
(check whether "boot_a" is "Boot" and "boot_b" is "Inactive" or vice versa, and choose correct partition for the next command)
Code:
edl /w /pboot_a patched-by-Magisk-boot.img
Thank you Renate for the help for me and other rooting people for such detailed explanation and a hard work!
One day I will make it into a YouTube video, so people would have easier times in the future!
