General notes sit on the first sheets of each discipline and along the edge of many plan sheets. They cover items the drawings do not show one by one.
Example: a general note says to provide blocking in walls behind all wall-mounted equipment. No plan shows the blocking, but someone must price it.
Read the general notes for your discipline and for the architectural sheets. Mark each note that adds cost or assigns work to a trade. General notes are easy to skip and they are part of the contract. Do not confuse them with keynotes, which point to one spot on a drawing.