During more calm and passive breathwork practices and controlled breathing exercises you find in Breath Hub it is very unlikely that you start hyperventilating or faint. All breathing exercises are designed to safely practice from the comfort of your own home.
During more active breathwork practices like holotropic breathwork, Wim Hof Method or Transformational Breathwork, some people experience hyperventilation and in rare cases they can black out. This is not something to be worried for, your body will always find its way back to homeostasis. It is however advised to practice these active breathing techniques under the professional guidance of experienced teachers and trainers.
The beauty of breathing and breathwork is that you are always in control. Whenever you feel uncomfortable, lightheaded or overwhelmed, simply come back to your normal breathing pattern and your physical and mental state will change accordingly.