Select the refresh button

When the USB port shows next to the Port drop down select connect.

Make sure you're on the Erasing & Programming tab

Select Browse and select the "Bootloader_FYSETC_SPIDER.hex" file from earlier.

Click Start Programming.

It should only take a few seconds to program the board.

Disconnect the power and USB-C cable. Remove the jumper on BT0 and 3.3v