Each phase in the process is simple to understand, but when all of the processes involved at the same time is beyond what most humans can manage with pencil and paper. Except for the very smallest shops, a computer system is an important requirement for production planning. Planning is the complete foundation on which the manufacturing system stands. Planning refers to the scheduling of work orders and the materials and outside services needed by work orders. Effective planning means having the materials on hand when needed and working on the right things at the right time.
Planning is fundamental.
Without it you can never escape the expediting nightmare. The answer is no. Oh, people have tried to do so with every possible software solution imaginable, but they have all failed. Because the manufacturing environment is one of constant change. Customers do have emergencies and change due dates or product specifications or need rush orders.