According to the relevant provisions of the patent law and the detailed rules for the implementation, as long as you have three characteristics of novelty, practicality and creativity, you can apply for a patent. Obviously, many business methods have these characteristics, and there have been many such patents in developed countries, such as the United States and Japan. For example, the patent used by Dentsu Corporation of Japan to sue some domestic e-commerce companies is a typical business method patent. Companies like Amazon have mastered a large number of similar patents. For example, Dell applied for the patent of "the process of configuring software in make-to-order production" for its unique direct selling model.
Looking back, the current business method patents can include telecommunications, finance and finance, ordering and transportation, and all patents related to Internet applications and e-commerce. There is no doubt that the ERP system you mentioned can be patented.
There is no contradiction between patent and copyright (which should refer to software copyright here), because the content of protection is different. If ERP applies for patent, the core of protection is process and method, not the content of software program. Software copyright registration is to register the coded content of software, so both can apply at the same time.
Last month, I represented a patent for an operating cost management system, which is the ERP system you mentioned.