It Turns Out, They Are the Protagonists - Chapter 451: Wrath of the Heavenly Court p1

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.

In a person’s life, three percent depends on hard work, seven percent depends on talent, and ninety percent depends on appearance.

Ding Mu, originally an ordinary person with a little handsome, a little money, and a little smart, could only live an ordinary life with a little luxury and a little glory.

By chance, Ding Mu wanted to download Meitu Xiuxiu, but got a real-life beautification system of aliens.

- Description from novelbuddy

Father: “Qianqian, he may be a quadriplegic but as long as you agree to marry him, our company will be saved!”

Freak Xie Ao Yu originally had no way of cultivating battle qi but, by accident, he got a mysterious godly pellet and he received a supreme emperor blade. That changed his destiny and from then on, he felt the real meaning of life and he made original time and space related battle skills and decisively battled ancient, huge clans and hundreds of continental clans in the Qi Ao continent.

Clouds formed with a flip of a hand and rain formed with another flip. He left the strongest mark in tens of thousands of years of history and created glorious chapters about a tyrant’s anger, blood shed for thousands of miles, the skies hissing from mad blades, and the allegiance acknowledgement of all times.

- Description from Novelupdates