I hope they realise screaming till they are blue in the face is not going to make it apear
They do soon learn that, just so long as screaming till they are blue in the face does not make it appear. But some children still scream themselves blue in the face anyway, out of sheer frustration. So if you expect that being consistent will stop the child screaming you may live to be disappointed. Some children handle frustration more calmly than others, older children usually do it better than toddlers but not always, and it's not something you get to decide.
I’m going to need more info. How does a stoic parent react to the fact that a meltdown is occurring because the red plate is in the dishwasher from breakfast and you have served lunch on an unacceptably not red plate?
That's where having a child with autism worked in our favour. If the plate was red, the child was happy. So E worked for us - or rather, making damn sure the plate was always the same no matter what. Bless.
If me sticking to the rule makes me mean though you are eating off the blue plate if not ok their choice but I am not swaping for a red plate same for food. They will not get their way throwing a tantrum
Two of the most useful rules of parenting are "choose your battles" and "don't sweat the small stuff". Trying to be even more rigid than a toddler isn't good parenting. It will turn you into a pair of tantrumming toddlers.
Distraction and letting things go are often more effective.
don't scream or shout more cry to the point I throw up just hearing or reading something sad or panic to the point I don't know what to do in situations out of my control
Oh dear, it sounds as if you have a problem with emotional regulation yourself. Life with children is full of situations you don't control. Children are like emotional amplifiers and you might explode.