How does 220 kN of engine thrust create the 700 kN required to maintain the altitude of an A320?
The engines only need to overcome the induced drag to remain in the air, which is a result of the lift but usually much smaller on the order of 1/20 for a modern jet. This ratio is specified as lift to drag or L/D. It is a vital performance statistic of an aircraft. Why? Wings are weird and complicated, there is not a simple 100% correct answer.

Only a rocket needs thrust equaling gravitational force since it has no wings! (L/D = 1/1)