1. An information processing apparatus, comprising circuitry to: read, from a first memory, a model common function file defining one or more common functions that are common to a majority of a plurality of models of an image forming apparatus and one or more setting items corresponding to the common function, and one or more model specific function file defining a function specific to one of the plurality of models of the image forming apparatus and setting items corresponding to the model specific function; and combine the model common function file with the model specific function file to generate a combined function file.