One Planet for Everyone! Building Science and Technology Civilization at the Beginning - Chapter 385: The world shakes! Forever and Ever!

Hey? Why is there a HP Bar and a Title above your head? Why do you know magic? Hey, why are there people slashing their swords at me!? What’s wrong with this world? Why is it so much like an RPG!? HEY!!

“Hey, Yoshi-kun. I think you’re——”

Hearing that voice for the first time stopped me in my tracks. On my way home from school. On the playing field of our junior high, and at the bookshop in front of the station. And then in the empty lot where the white cat slept. Shiina Yuki, the strange girl who somehow knew all about me, always approached me like that.

We laughed, cried, got angry, held hands. Again and again, we repeated those disappearing memories and ephemeral promises. That’s why I never knew. I never knew the value of Yuki’s smiles or the meaning of her tears. Nor even the singular sentiment behind her many ‘Nice to meet you’s.

This is a captivating, heartrending tale of meetings and partings.

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.

“You want to steal my genes then leave?” He grabbed her and tried to force her to hand over the child that was born three years ago.

She never had a baby? Then conceive one!

The delusional CEO’s desperate love. Her inability to resist as she fell deeper.

OK, the baby is born. She handed it to him and left!

Yet, he had her hog-tied and thrown onto the bed. Furiously boiling with anger he roared, “Woman! Who said I only wanted one?”

- Description from Novelupdates