# Turning a 2 wheeled robot 90°

i got a task for which i need to drive a certain distance and move around an object. I finally managed that my robot goes almost straight but i think its enough. But now i gotta tackle the problem how to turn my robot by 90° at certain points. Can someone give me some advise how i can program the turning of the robot? For measurements i got wheel encoders and an IMU but i dont have any experience using the IMU. Thanks you for reading :)

$$\theta = \omega_z*\Delta t$$