Dynamics 365 as a whole may not be available for on-premise deployment, however, you may consider using some on-premise version of D365 applications such as Microsoft Dynamics NAV, Microsoft Dynamics AX, and Microsoft Dynamics CRM. For on-premise deployment, businesses need to purchase software licensing and maintain a robust infrastructure for database management. Besides this, updates need to be rolled out and managed by your internal staff. Though Dynamics 365 on-premise deployment provides better control over the data, you may not access Cloud-based services and features such as Power Automate (Flow), Power Apps, Power BI, Web Portals, etc.