find (one's) feet
To reach a level of comfort in a new situation. It took a while, but I've finally found my feet in my job. I know you're nervous, but all freshmen are—you'll find your feet at school, don't worry.
find one's feet
Fig. to become used to a new situation or experience. She was lonely when she first left home, but she is finding her feet now. It takes time to learn the office routine, but you will gradually find your feet.