Spatial Peasant Girl: These Mad Darlings Are Delicate and Gullible - Chapter 320 - : Limited Settings

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

The first time they meet, she bumps into him. The second time they meet, she agrees to a marriage contract in exchange for his help in her bid for revenge. But… he becomes addicted to loving her.

During his first attempt, he flies a helicopter domineeringly; in his second attempt, he arrogantly removes all his love rivals; in his third attempt, he tries to tie her down using a cute child. Youxuan replies with a plain resounding ‘no’ all three times.

In the end, Shan Hanjie takes one look at her, grits his teeth, and plops onto the ground. “Babe, you dropped your prince charming, please bring him home!”

The amiable looking patriarch is gazing at a stone monkey: “Wukong, what do you want to learn from me?” “It’s all up to master’s instruction.” The stone monkey respectfully replied: “As long as I will be able to beat up Tathagata, then it’s alright.” One hundred years later, the stone monkey defeated Tathagata and ascended the throne, becoming the Jade Emperor.

- Description from rhadoko

Liu Ergou grew up in the village and studied medical skills with his grandfather. After his grandfather died, the responsibility of treating the villagers falls on him. But an accident bestows upon him an inheritance from his great-grandfather, which sets him on the path to invincibility!