How did you get on my fire escape ? Here does fire escape mean my address?

Thank you in advance.

A fire escape is basically a set of outside stairs on a building, to be used to exit in case of fire.

Sometimes a fire escape is designed so you can only get onto it from inside the building, like this:
Sometimes there is a ladder that you can lower to the ground from the fire escape (or close enough that you could jump
down), but it doesn't go all the way to the ground (to prevent thieves from using it to enter the building.) If you looked out your window and saw someone on your fire escape, you might well ask how they got there.
Students: Are you brave enough to let our tutors analyse your pronunciation?
Kathy: Yes, Kathy69, John’s ex -girlfriend. I have to talk to you!
Marni: What are you doing here? How did you get on my fire escape ?

Could you please explain to me what does get on mean ? Sorry , I can't understand the function of get.

Thank you.

get on a fire escape

Here, the idea is roughly 'gain access to'.

eg There were so many people that it was hard to get on the bus.

Students: We have free audio pronunciation exercises.
 khoff's reply was promoted to an answer.
Thank you very much for explanation. Emotion: rose Actually , I've seen fire escapes but I couldn't understand why they are so short. So, they are short to prevent thieves. Emotion: big smile