A Virtual Private Cloud (VPC) in your AWS account will allow your application servers and development environment to directly connect to MongoDB Atlas while remaining isolated from public networks. Using a VPC peering connection allows MongoDB to automatically scale your application tier without having to manage your database firewall rules.
This tutorial in Introducing VPC Peering for MongoDB Atlas blog post will show you how to set up your VPC both in Atlas and in AWS.
Create an AWS account. Create a VPC. Enable “DNS hostnames” on the VPC (optional). This will make it possible to immediately resolve the hostnames in the peered MongoDB Atlas clusters VPC to their private IP addresses (otherwise propagation can take up to one hour).
Launch instances that you can SSH into. Download MongoDB shell software onto those instances to confirm connectivity.
Create a MongoDB Atlas account and deploy an M10+ cluster.