If you are using CYW20719 eval board- CYW920719Q40EVB-01, then you will have recover and reset buttons on board. Press SW1, then SW2 and release SW1, the device will enter in recovery mode. Then you can start sending HCI commands/program the device.
If you are using the CYW20719Q40EVB, the CTS is high when you plug the board to your computer. Then you can excute a reset with the reset button.
If you open the HCI UART port with a UART terminator on your computer, the CTS will pull down.