After the method is invented and patented, can it not be used by other enterprises or individuals?

Yes, exactly, after the patent is granted, others can't produce this thing for commercial use. You can sign a licensing contract with others and pay the patent royalties to the patentee before you can use it.

patent law of the people's republic of china

Article 11 After the patent right for invention and utility model is granted, except as otherwise provided in this Law, no unit or individual may exploit the patent without the permission of the patentee, that is, it may not manufacture, use, promise to sell, sell or import the patented product for production and business purposes, nor may it use the patented method and use, promise to sell, sell or import the product directly obtained according to the patented method.

After the design patent is granted, no unit or individual may exploit its patent without the permission of the patentee, that is, it may not manufacture, promise to sell, sell or import its patented product for production and business purposes.

Article 12 Any unit or individual that exploits another person's patent shall conclude an exploitation license contract with the patentee and pay the patentee the royalties. The licensee has no right to allow any unit or individual other than those stipulated in the contract to exploit the patent.

But whether this method is infringing or not needs to be judged according to the patent claim of the other party.