How to join the CIA or the FBI?

Before you become an American citizen, you have to take an exam to test American customs, geography, politics, laws and so on.

You have to live for five years after you become an American citizen, and you will still be an immigrant after you get your nationality. The FBI doesn't seem to accept immigrants.

Even if you receive a letter from the FBI, you can't count 100% as success. You must confirm it from immigration.

According to the current law in the United States, if you want to join the FBI, you must be an American, have a college degree, or have served as a captain in PD and above law enforcement departments for more than five years, or you know eight languages or something similar in some way, then he will agree to your joining. But the CIA will conduct a secret and comprehensive investigation on your family in China, and your family can't have any criminal record. At the same time, there are many restrictions on your physical requirements.