I Can Make Everything Level UP - Chapter 1: New Life (1)

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.

Like many medical students, Li Yong just succeeds finding an intern job in hospital with great efforts and yet still is going broke. He even has no money to pay the rent. However, by coincidence, he acquires a magic power of clairvoyant vision and rich experience from 80 medical experts, all because of a pendant passed down from his parents. With the magic power, he can see through human’s skin and finds out any illness beneath without any physical touching or examination! Since then, his life has been tremendously changed. Love, fame and wealth become within reach for him…

- Description from Novelupdates

In the world of dragons and snakes, the talented but congenitally sick martial arts master was reborn as the sole heir of the 19th-century Canadian manor owner. He thought he would make money by practicing boxing, but he took advantage of the industrial revolution to become a giant of the times. The opened template.

In the end, the original owner was a hopelessly sick and consumptive ghost! I am still a bastard having an affair with a gardener…

Wait, what’s up with the claw?

James Howlett looked at the bone claws protruding from between his fingers, and became more and more worried about his future.

- Description from novelbuddy

Volume 1 (Set between volumes 13 and 14)

A series of short stories set before the events of volume fourteen including how Team GROUP was formed.

Volume 2 (Set between volumes 16 and 17)

A series of short stories including two separate meetings between Touma’s and Mikoto’s parents, two tales involving two of the Level 5s of Academy City, and other funny stories involving some of the characters.