It is commonplace to put salt in water when boiling most foods. The reason why you put salt in with boiling water and vegetables is to help them retain moisture.
You put them in the water after the it is boiling not before
noddles
gf
Probably what they wanted to say is something like "Do not put your hand into the boiling water."
No, it is not safe to put boiling water in a Nalgene bottle as it can cause the plastic to deform or release harmful chemicals.
to put in boiling water
It melts
When you put a spoon in a pot of boiling water, the agitation caused by the spoon disrupts the formation of bubbles that are necessary for boiling to occur. Without these bubbles, the water temperature doesn't rise quickly enough to reach the boiling point, preventing it from boiling.
adding salt raises the boiling point of water which can help speed cooking time.
Some people would say that lobsters do make a "squealing" noise when cooking if they were alive. There have been personal experiences when lobsters did scream when I have put them into a boiling pot of water.
Put it in boiling water