How do people prototype circuits without getting shocked?
It’s a common misconception with beginners that a 2A power supply will force 2A through anything that touches it.  This isn’t the case.  Most power supplies are (more or less) constant voltage, so the resistance of the load determines what current flows.  The human body has a relatively high resistance and so low voltage circuits can be handled with only tiny currents flowing.  In my experience I can’t feel any current below about 1mA and for me that happens at about 100V (don’t try this at home).  Even for low-voltage circuits it’s good practice not to handle circuitry when it’s powered, as it’s easy to cause shorts or disrupt sensitive signals.