Is "dive in" a phrasal verb? When's it used?

Native speaker’s answer
Rebecca
"Dive in" is a phrasal verb! It means to start doing something fully and enthusiastically. It's commonly used with food but can also be used when you're starting something for the first time and you're a bit nervous or unsure. If you "dive in," it shows full commitment. It's also used for swimming and means to plunge one's body into the water. Ex: They sat down at the table and dove into the meal in front of them. Ex: You have to dive in and not be afraid of messing up when learning a new skill. Ex: I'll dive in and swim a couple of laps.