There are two ways to convert a three phase motor to single phase.
Rewinding the motor is one, you will loose power, as more iron pack is required on monophase motors for the same power.
The other way is to use an inverter, which will give you 3x220 volts instead of 3x380 volts (or whatever voltage you have, read the data in your motors) . You will have to re arrange the connections from star to triangle. This works for 220-380 motors, up to 3 hp appox.
Technically an inverter may or may not be VFD
, nowadays all inverters do have VFD cappabilities as well as slow start. You may use them or not.
But this is the way to achieve your requirement. Remember: up to 3 hp.