How can one start writing mutant oc fanfiction?

In this world, Planet Earth had undergone great changes and humanity is faced with extreme danger. Luckily, humans have something called the Heaven Dao software. After downloading the software, Zhou Hao received one million luck points and used it to open a mystery box and obtain the “108 Levels of Dragon Elephant Wisdom Technique”… Also, Zhou Hao realized that with enough luck points, he could even get his crush to sleep with him! In this world full of Insect Race warriors and Demon Race experts, it is ridiculously easy for Zhou Hao to accumulate luck points…

A Drunken conversation between the heads of the Marvel-verse lead to a decision to save the life of a MCU version of Harry Potter destined by the fates to die. How? By giving him the powers of a video game character. Currently at 650K+ words

The whole world mutated. Mysterious resurrections happened in real life. The Tribulation descended. Everyone would awaken the ability to rule over beasts at the age of 18 and obtain a Lord Space of their own. After one month, their Lord Space would materialize and they would become a Lord. When they awakened, each Lord would obtain a summoning pool to summon their own troops. They had to plunder resources, strengthen their troops, expand their territory and defend themselves against the invasion of demons! Ren Qi recruited a mutated succubus from the very start. She could keep ascending until she became a fallen angel! Someone exclaimed, “Someone managed to recruit a succubus?” Another person said, “Why are you envious of him? Succubi don't have much combat ability and are weak. When his Lord Space materializes, he will most likely be consumed by the demons.” Someone said, “Hahaha, I awakened a top-tier troop, the Golden Tiger. I am invincible.” Not long after, Ren Qi’s territory expanded to the Warring Nation Level. A group of fallen angels stood beside him as they looked down on all the demons. The weakest fallen angel was an existence akin to a demigod.

Lin Qi transmigrates to a world of immortals. In this world, there are sword immortals who can behead a person from a thousand miles away, peerless great demons who burn mountains and boil the seas, and ancient gods and devils who can divine the heavenly secrets. As a disciple in charge of miscellaneous chores in the Skysword Sect, Lin Qi doesn't have any cultivation talent. A hundred years had passed in a flash, and seeing that he has nothing to do with such a great world, Lin Qi is incomparably depressed. Just as he is about to die of old age, he suddenly awakens a cultivation system. Unlocked One-Click Cultivation System: Limitless cultivation speed boost, one major realm per second! Unlocked One-Click Technique Practicing System: Cultivation technique instantly maxed out. Cultivate 10,000 techniques at the same time! Unlocked One-Click Clone System: 100% of the actual body's strength. Can self-destruct, can teleport, can fuse! As a result, Lin Qi begins to cultivate again with his hundred-year-old body, becoming invincible under the heavens.

Reborn in a DC universe as a Marvel Mutant. Fanfiction by Grey Dragon https://forums.spacebattles.com/threads/marvel-mutant-in-dc-oc-in-au-dc.723367/reader/

100,000 years ago, a meteorite crashed into Earth, granting a 17-year-old caveman the power humans have craved for millenniums, immortality. Though originally a savage and cruel caveman, millenniums have let Acheron refine himself and surpass the epitome of Humanity, basically, a god on Earth. With his power, he mastered all forms of combat, every language, all the arts, and much more. He sometimes created empires, sometimes built empires, sometimes destroyed empires, at times, even his own. Today, mutants with superpowers walk among the public, it is kept a secret by the governments throughout the world, and events pertaining to them are covered up but doesn't stop Acheron from interfering with their plans. 2 months ago, his oldest adopted daughter passed away, she was 96 years old. Though he cherishes all the children in his family, she was without a doubt, one of his favorites. "Her last wish was for me to have a normal life but what do children do in this era?" Acheron asks one of his adopted sisters. "They go to school, Lord Acheron," she says. "School? Will it be entertaining?" he asks, "It would at the very least be a new experience" she replies. "Make it happen!" he orders. " Yes! I will do it immediately, Lord Acheron" she says. He, who was there when the first Homo Sapiens migrated out of Africa and existed way before the wheel was created, will let nothing interfere with his daughter's last wish and will slaughter anyone that stands in his way. P.S this is not a Marvel or DC fanfic. I will also be posting this on RoyalRoad.com (Cover photo was taken from Google)