Yes, AWS Direct Connect can be configured with a router to use real IP addresses. The router will need to be configured with the appropriate IP addresses and routing rules to allow traffic to flow between your on-premises network and your AWS resources.
AWS provides sample configurations for popular router vendors on their website, which can be used as a starting point for configuring your own router. These sample configurations include examples of how to configure IP addresses and routing rules.
Keep in mind that the specific configuration you will need to use will depend on your network topology and specific requirements, so it is important to review and modify the sample configuration to fit your needs. It is also recommended to consult with a network or AWS expert to ensure that your configuration is secure and meets best practices.