MTL - Conan’s World Stand-in - ~ Let's talk about a side story later, let's play escape room

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.

Uzumaki Naruto wakes up one day to find out that his life has been turned into a RPG game, thanks to his 'Gamer' ability. What should he do about this? Smart(er) Naruto. Elements of Romance Games included in later chapters, so possible upgrade to M later

Upon waking up, Ruan Xia had transmigrated into a webnovel that she had stayed up all night to finish reading. She had become the villain’s mother.

In the novel, after the death of her first husband, the original owner of the body had hooked up with a Mr. Perfect at the fastest possible speed. Worried and discontent that her son from her first marriage would become a burden on her, she heartlessly abandoned her son.

Having once held the best quality script and informed of future events, Ruan Xia looked at her still alive first husband as well as her future villain son. She sighed. She wanted to apply for a different script!

When I died I meet with this being who offered me a new chance at life, to actually become someone important and I agreed and was reborn as none other as the First Man.But to think that everything that I ever knew was nothing more than a lie, what am I going to do to survive in such a world?