Read the datasheets. C232HD is configured as COM port, C232HM as non-COM-port peripheral. The former is installed as virtual COM port automatically, the latter would need reconfiguration with the FTDI tool.
Yes, the datasheet of C232HD clearly shows that it can be used to bridge USB to UART.
It is interesting to know that C232HM can also be used to bridge USB to UART provided it is reconfigured with the FTDI tool. I guess this reconfiguration is needed only one time using and then we can use it with different setups without FTDI tool, right ?