Will all the brake fluid leak out if one of the chambers is leaking?

Good evening,

The answer is no. Only the chamber with the leak will drain and the other will remain at its level.

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

I attached the diagram of the system for you when you are looking for leaks.

Roy

But will the brakes still be firm or not? And how long can someone drive with the spare circuit?

No, the pedal will be half at best and the stopping distance will be greatly increased.

I would not drive it that way at all. I would get it fixed ASAP.

Roy

So no floor touching.
I think it gives the same symptoms of failing master cylinder if i am not wrong.
Well, how far can you go if one of the circuit is broken?

Again, I would not drive it with the pedal that low. It is an extreme safety hazard and needs to be repaired.

I would not drive more than the distance to a repair shop.

Roy

Yes, i know usually in single circuit system ince the fluid is over the brakes stop working.
Does it take the same time for the dual system to stop working or take longer?

When you have only one portion working, the pedal reaction time and distance for stopping are greatly increased as I stated before.

Roy

Thanks Roy.

You are welcome.

Always glad to help.

Roy