Boil your water/stock/broth, pour it into a bowl - add noodles. Cover, let stand for 2 or 3 min.
All the ones I've had this is what you do... you are not 'cooking' them, just softening.
and Hi and Welcome to DC wynhgy!
oh oh, not true, just remembered there was one where I boiled the broth on the stove, added the noodles and simmered for 2or 3 min.
Water boils at 100C, 212F.
I go by sight.
Ross