On the latest data sheet, when boot loader from UART1, Table 79 show 4 pins are used,

But on reference manual table 8-1 as follows:

Only two pins are needed. Which one I should to use, if the UART1 port does not use CTS and RTS signals, is boot loader still to talk the device? Where I can find more information regarding the ROM bootloader?
When boot from FlexSPI, it lists a hyper flash as follows:
Is the ROM boot loader works with QSPI flash on FLEXSPI_A or FLEXSPI_B port, if yes, how it behaviors? Which IC is selected first? FLEXSPI_A_SS0_B or FLEXSPI_B_SS0_B? What is required connections?
Any help is appreciated! Thank you in advance!