I'm working on a project which will use many of the functions of this board. I'm trying to use the attachInterrupts() function and interrupt protocols in order to trigger events. The store site says that "all digital pins" are external interrupts however the information on other nano boards online seems to conflict. For example the nano 33 iot and nano every also say all digital pins are interrupts but they aren't and there are diagrams showing which pins are actually interrupts floating around.
Please note the Arduino Nano 33 IoT and Nano Every are two completely different devices. They have nothing in common other than the physical form factor of the board.
Regarding the interrupt, I would just write a very simple sketch and test it when you doubt the information from the store page. Sometimes there are mistakes. For this question, this should be easy to find out.
According to the datasheet of nRF52840 "All peripherals support interrupts. Interrupts are generated by events." In order to confirm it will be best to just check as @Klaus _K suggested.