Step 2: Create a Network Firewall rule group to use in your policy
To follow this tutorial, you should be familiar with AWS Network Firewall and know how to configure its rule groups and firewall policies.
You must have at least one rule group in Network Firewall that will be used in your AWS Firewall Manager policy. If you haven't already created a rule group in Network Firewall, do so now. For information about using Network Firewall, see the AWS Network Firewall Developer Guide.