1.
If you get into a particular kind of work or activity, you manage to become involved in it.
He was eager to get into politics.
PHRASAL VERB : V P n
2.
If you get into a school, college, or university, you are accepted there as a student.
I was working hard to get into Cambridge.
PHRASAL VERB : V P n
3.
If you ask what has got into someone, you mean that they are behaving very differently from the way they usually behave. ( INFORMAL )
What has got into you today? Why are you behaving like this?
PHRASAL VERB : V P n