I Don't Know the Original, I'm Too Busy Trying to Make a Living - Chapter 73

Yang Yi crossed over the world with a storage space with him. He ended up in some desolate wilderness populated by flying beasts and dangerous predators and also crawling poisonous bugs and snakes. To prevent getting bitten in the ass by venomous bugs when going to the toilet, let the great infrastructure begins –
Our goals are:
Eat well till full stomach.
Having clothes to wear but also being good looking.
To have a house that could cover all seasons.
Roads that leads to every place; develop agriculture, industry and commerce together.
No shortage of both material and spiritual needs.
He was DETERMINED to build a safe, comfortable and prosperous modern city in the wild world together with the native tribe with max efforts.

- Description from Novelupdates

Zhou Rui had just turned 20 when his life took an unexpected turn. He was hit by a truck one day. Just as he was convinced he was about to die, something strange happened. Instead of waking up in the afterlife, he opened his eyes as a baby. Later, he learn he had reborn as Lumien Ofnir, the youngest son of a baron.As Lumien grew up, he realized this world was nothing like Earth. Magic was real, and creatures like goblins, orcs, dragons, titans, and other mythical creatures were part of everyday life.Fortunately, in this dangerous world, Lumien received another blessing. It was a system.Follow Lumien's journey as he begins to explore this new world with the support of a Harem System. The mysterious cheat that allows him to copy and develop the magical powers of any woman he has slept with.[Author’s Note: The earlier chapters might feel slow and boring, but I promise it’ll all be worth it once the pace picks up.]

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.