I want to flash stock rom

And someone told me that I have to flash another csc than what I have now.I have s8 plus exynos, rooted with magisk and twrp. Do I have to flash another one? I watched a video of Max Lee saying that it's not good to flash csc... What should I do? I dont want to brick my phone. via /r/GalaxyS8 https://ift.tt/2FL4iHA