Qin Dynasty: Who offended my frail and sickly minister?

Time travel + no romantic pairing + has a system (but the system doesn't have much screen time).
Zhou Wenqing unexpectedly transmigrated to the Warring States period, a time of great turmoil. To make matters worse, upon opening his eyes, he found himself severely injured. Then, in the blink of an eye, he remembered the original owner's identity as a "spy" sent by the State of Han to the State of Qin, and he was completely dismayed.
Zhou Wenqing originally had no intention of flapping her little butterfly wings. She tried countless times to recklessly see if she could go back, but was left behind by one accident after another.
"We're already here, what else can we do but survive?" Zhou Wenqing sighed helplessly.
Then, without realizing it, Zhou Wenqing somehow ended up like this—
King Ying Zheng of Qin: My wise minister! Who has displeased you again today? Don't keep it bottled up inside and make yourself sick. I will exterminate their entire family for you!
Prince Fusu: Teacher, Fusu doesn't understand this, this, and this. Please teach me again and don't abandon me, okay?
Prince Huhai: Waaaaah~ Teacher, I was wrong. If you're angry, just punish me. Don't keep it inside, or Father will beat me to death!