Brickset API documentation is available here: https://brickset.com/article/52664/api-version-3-documentation/
getInstructions(setID, setNumber, key = getOption("brickset_key"), ...)a data.frame with the instructions.
the ID of the set (see data(legosets))
the set number from on the LEGO box
the Brickset API key.
other parameters passed to getUserHash including
the Brickset username and password if they are not available from
getOption('brickset_username') and getOption('brickset_password').