the ropes
The details or knowhow about a specific situation, task, job, or role. I know there's a lot to take in, but your partner has been here for over 10 years and will show you the ropes. This class is intense! You're expected to know the ropes from day one.
*ropes
Fig. knowledge of how to do something; how to work something. (*Typically: know ~; learn ~; show someone ~; teach someone ~.) I'll be able to do my job very well when I know the ropes. John is very slow to learn the ropes.