Boiling Water

Boiling Water I have to boil some water But I’m not sure just how My wife does all the cooking But she is not home now I start out with the water Should it be cold or hot I checked in an old cookbook Directions? There were not I know I have a gas stove Do I turn the flame up higher Or will it boil with low flames As long as there is fire I see some bubbles forming Could it be boiling yet What does it mean by “rolling” How much hotter must it get The bubbles pop and splatter I guess it’s boiling looking The only thing the matter I forgot what I was cooking