dive into

US /daɪv ˈɪntuː/
UK /daɪv ˈɪntuː/
"dive into" picture
1.

to start doing something with a lot of energy and enthusiasm

:
She decided to dive into her new project with full commitment.
Let's dive into the details of the proposal.
2.

to jump headfirst into water

:
The children loved to dive into the swimming pool.
He took a deep breath and dove into the cold lake.