Gaining

For people trying to gain weight, is it better to have breakfast and get those extra calories?

Or is it better to skip breakfast, slow your metabolism then allow that hunger to make you eat more later in the day?

Less calories seems counterintuitive but there are all kinds of articles on "how skipping breakfast makes you fat"

A big, unhealthy breakfast will make you gain more than no breakfast.

I usually have a big bowl of cereal or fix 10 packages of instant oatmeal. Today I'm having 24 packages 3100 calories. Now that is a big breakfast

There is no such thing as slowing metabolism, if you skip a meal you will essentially waste calories. The thing about skipping breakfast contributing to weight gain is because when you don't eat for long you get so hungry you tend to overeat during next meal.
If you're gaining on purpose you should eat regardless if you are hungry or not. In the end it is all about calories spent vs calories consumed and eating all the time definitely helps with that.