This tutorial explains how to add AWS Secondary Private IP in EC2 Instance including Windows and Linux Instance.
What is Secondary Private IP address ?
Secondary Private IP addresses are nothing but an additional IP address used with the Primary IP address on the same Network Adapter.
You can add secondary Private IP address to all Network Adapter ( or Elastic Network Interface (ENI) in terms of AWS ) associated with the EC2 Instance.
Read more on
https://devopsmyway.com/adding-aws-secondary-private-ip-in-ec2-instance/