Naming Technique of the Night - Chapter 931 - 573, Three Battles with the White Bone Demon

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.

A world where waves of monsters descend every night...A world where only the strong can survive.Axel, a burned-out man from modern Earth, wakes up in a desolate wasteland with nothing but a strange “Harem Settlement System” with him.Given the power to build, command, and grow stronger, he sets off to carve out a safe haven in this broken world. But as his settlement grows, so does the number of beautiful and deadly women drawn under his blanket-ahem!-banner.Witness Axel's journey, rising to to the peak. From a simple, lone survivor to becoming the Wasteland Overlord. With the help of the loyal, dangerous, and irresistible thirsty harem girls!

Six years ago, the legitimate daughter of the Chu Family was schemed against by her half-sister and was forced to marry the Princely Heir, who was blind and not long for this world.Fortunately, her medical skills were excellent, and she detoxified the Princely Heir.Who would have thought after he came back to life, the emperor would actually want to bestow a concubine upon him—and this jerk didn't even refuse.Furious, she left a divorce letter and then set the Prince Residence on fire, fleeing in haste.Six years later, the same Princely Heir remained a lonely man, with all his old servants worrying their hearts out.One day, upon encountering a Little Baozi on the street who looked strikingly like the Princely Heir, they instantly burst into tears.“The Prince Residence has a successor! Princely Heir, please come back with us to the Prince Residence quickly.”Who knew, Little Baozi disdainfully said, “Not interested.”“Princely Heir, the Prince Residence is immensely wealthy...”“My mother is the wealthiest person!”“Princely Heir, the Prince Residence is extremely safe...”“My mother is the Martial Arts Alliance Hierarch!”“Princely Heir, the Prince Residence has powerful armies...”“My mother is the heir to the Nanduan Kingdom!”Suddenly, a faint voice came from behind: “Then, does your mother need an Imperial Consort? I think myself quite suitable.”

Travel across different worlds and become a fallen aristocratic lord. With the help of the proficiency panel, you can start your liver experience with the ancestral knight breathing method, follow the wizard’s footsteps step by step, and embark on a bizarre and mysterious journey.

- Description from novelbuddy