If your IDE doesn't see Arduino R4 and you have tried everything to make it work. This is the link for resetting the board --> https://support.arduino.cc/hc/en-us/articles/9670986058780-Update-the-connectivity-module-firmware-on-UNO-R4-WiFi
There are a few methods. Personally, I needed to use the last one, because my new Arduino R4 just miserably crashed. After resetting, and uploading the newest firmware using the Firmware update button, everything worked flawlessly.
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