Brother, just how powerful is our family?

Qin Feng, who was unemployed upon graduation, was bound to a mysterious system at the lowest point in his life.
With limitless energy conversion and leading technology across the universe, he chose to keep a low profile—traveling to Africa and spending two years building a vast underground empire.
Above ground lies a luxurious manor; below, a technological kingdom. An army of 300,000 cyborgs, twelve interstellar warships under construction, and a nuclear arsenal hidden deep within.
He had planned to continue playing it safe and developing his strength, until his younger sister, Qin Yao, came to Africa to visit relatives and livestreamed: "Brother, just how powerful is our family?"
Is a telecom fraud group in northern Myanmar livestreaming provocations? A 24-hour special forces cross-border rescue operation resulted in the annihilation of 2,000 armed individuals.
Is the US carrier strike group putting pressure on us? They test-fire an uninterceptable intercontinental ballistic missile right on our doorstep, and then set off a nuclear explosion.
The world was shocked, and countries trembled.
Returning home in glory, Qin Feng looked at his backward hometown and his compatriots who had left their homes, and made a decision: if we're going to play, let's play big.
Chip bottleneck? I developed my own carbon-based quantum chip.
Brain drain? I'll invest trillions to build a university town.
Is Henan being targeted? I'll make Henan Province the global heart of technology.
[Underground Empire + High-Tech Military Expansion + Rise of a Great Power + Family Warmth, No Mary Sue or Suppressed Feelings, Ruthless When Necessary]