If 3 phase machine then 3 phase power hooks up to RST terminals.
If single phase to a VFD, you cannot hookup a VFD directly to a 3 phase lathe and have it work, if you want to go that route you need an RPC. There is a way to strip out the high voltage wiring to the forward reverse contactors and use these to switch the low voltage forward reverse inputs on the VFD, but the total install is more complicated and requires some rewiring of the lathe control board, wiring to the motor, etc. I have put together some notes on how this is done that I can send to you if you PM your email address. Since I do not have a 1440GT I am basing this on pictures and the wiring diagram, you do this at your own risk and need some knowledge of basic electrical wiring. The VFD needs a braking resistor and a speed pot, you need to program the VFD per a parameter file that I can supply, but may require some tweaking.
I am not sure why individuals are being sold 3 phase machines and a VFD, without some forewarning that you just connect them up and you are off and running,. In particular on a lathe, it is much more dangerous if done incorrectly.