Like here, in 1:18 Is there a name for this? technique? How do I train that kind of voice "switch"
That is a yodel. A yodel is when you quickly lengthen or shorten the vocal chords to create a rapid change in the register of your voice.
(One quick point of terminology: typically, when we say that someone is yodeling, we indicate that they are using this technique to go back and forth between their chest and their head voice rapidly. I have not encountered a great term-of-art for a single yodel, but when I have used the term in the singular with vocalists and speech pathologists, no one has been confused so far.)
Yodeling is also one of the primary vocal techniques utilized by Roomful of Teeth. (It starts before the 20 second mark on this song.) They combine world vocal styles into something truly new.
At 1:18 I don't actually hear anything that I would describe other than a "squeak". The technique required here is just good closure in the high register, pliable support and, if still necessary from the starting pitch, good register transitions so that you can make that brief glissando smooth and effortless in character.
So it's sort of demonstrating solid basics. It's similar to "how do I make a fast kick without falling over" when shadow boxing. There is no specific technique or skill to it that you would not be in constant need of anyway.