歼 8 has no two-seat model.
The design history of 1 and 歼 8 is high altitude and high speed, which was mainly developed to defend the MIG -25 of the Soviet Union and the SR-7 1 of the United States, and they are completely interceptor missiles. It is estimated that it will be ugly to develop a two-seat combat attack aircraft with such a design idea.
2. 歼 8 is actually an enlarged and improved version of 歼 7, and its operability is not much different from 歼 7. 歼 7 has a coach type: 歼 7 series. Both Jiao-11(the self-use version of K-8) and Gao -9 (Guihang Shan Ying) can train J-8 pilots.
I'll give you another link. You can look at the pilot training system of our Air Force.
/intro/platrainer/ 1.htm (wing of the air force, absolutely non-toxic, you can go and see if you like fighters).