First, establish the emotional state of Tony. Why would he be in such a desperate situation? Maybe start with his insecurities about his relationship with Steve. Then, describe the setting. Is it a tall skyscraper in the middle of a bustling city? Next, build up the tension before he jumps. Show his internal struggle. When he jumps, focus on the fall. How does the wind feel? What is going through his mind? For Steve's part, show his reaction when he realizes what's happening. You can also add in some side characters' reactions to make the story more complex.
Yes, it's extremely dangerous and can be fatal. The force of hitting the ground from any significant height of a building can cause life - threatening injuries.
You can't survive. A 5-story drop is way too high. The force of the landing would cause massive trauma to your body, and it's very unlikely you'd make it out alive.
It varies depending on the specific comic or media adaptation. But generally, it can span a significant amount of time with various plotlines and developments.