The titles are almost the same today, but the products differ considerably. Microsoft Dynamics NAV and Dynamics 365 (Business Edition) have evolved on various platforms, but from 2018, both are represented under the same umbrella brand Dynamics 365.
Frequently, the two solutions differ only in the number of users they could handle. However, their significance to a business should depend on how well they match the growth plans and the goals plans of the respective company.
Here are some of the differences between the two solutions
D365 for Finance and Operations Enterprise Edition (EE) - previously Dynamics AX - was mainly developed for large international organizations that are used in many places and possibly in different regions. If an organization has different accounting groups in enterprises within a consolidated business arrangement, the strong functionality of Enterprise Edition will exceed that of NAV.
EE supports centralized master data management (MDM) and a range of solutions that allow companies with a complex organizational structure to handle different standards. EE features transparency on inventory in international sites and on every area of business.

In addition to the comprehensive functions that are core, EE offers methods for sales, retail, professional services, and manufacturing and also public section. NAV is more of a solution that is unique.
In reality, EE was developed and designed as a complete solution for most manufacturing companies, from process manufacturing to contract engineer, with a vast range of functions and the flexibility to accommodate the requirements of business processes.
It goes without mentioning that EE, as a complicated solution, has AI functions and Business Intelligence. EE gains from the reporting and analysis tools in the industry by incorporating Cortana, Intelligence, PowerBI and Azure Machine Learning. It can also process large quantities of data without sacrificing performance.
These are some of the differences between the two Microsoft ERP Systems.