Where to get started in designing a 3 phase motor circuit
Three-phase motor control requires an inverter with circuitry to regulate the voltage in proportion to frequency. In addition, there must be an active current limiter, acceleration and deceleration controls and other features depending on the level of performance that is expected from the motor. The entire motor control package is generally called a variable frequency drive (VFD), motor-drive inverter or something similar. There are lots of them on the market and most of them provide excellent performance. Most also have auxiliary functions and interface capability for a wide range of operator or supervisory control systems.

Forget about designing that kind of equipment from scratch. Concentrate on determining the torque and speed requirements of the motor and the operator or automatic control functions. Search for VFD products and look at the resources that the sellers offer. Determine which sellers have a good reputation and good customer support in your part of the world.