Arduino Uno R4 WiFi comes with built-in Wi-Fi and Bluetooth capabilities, along with additional pins and a new, faster processor.

Reading about FTDI programming with a bootloader: RS-232 chips use the DTR pin to reset the chip and enter the bootloader's firmware-receptive window: The DTR signal is present on pin 20 of the 22- ...

Arduino clone broad, UNO not be able to download ? missing the DTR reset - xiaolaba/UNO-R1-R3-reset-circuitry ...