RP2040 upload fail

I am new in XIAO RP2040 and I have problems with upload the sketch (i.e. blink). I red in the wiki:

“If uploading the Arduino program fails, try holding down the “BOOT” button and then clicking the “RUN” button. At this point, XIAO RP2040 will enter boot mode (your computer will load a removable disk), and you will be able to upload the Arduino program again.”

What is the “RUN” button??? The “R” button is RESET, is it?.
I tried to follow the wiki instructions, but something is wrong (at me).
Please help me.
I. Vamos

In this Overview - Seeed Wiki wiki link it says:
Sometimes the XIAO RP2040 port may disappear when user programming process fails. we can solve this problem by the following operation:

  • Long press the “B” button.
  • Connect the XIAO PR2040 to your computer.
  • The computer will appear a disk driver.

At this point, the chip enters Bootloader mode and the burn port appears again. Because the RP2040 chip has two partitions, one is the Bootloader and the other is the user program. The product will burn a bootloader code in the system memory when it leaves the factory. We can switch modes by performing the above steps.

Thank you very mutch for your answer. Finaly my problem is solved!