In this example, I will create a resource group based on EC2 tag names of PackT:

1. From within AWS Systems Manager console, I select Find Resources from the left menu:

2. Within the Resource query section, I will select the AWS::EC2::Instance from the Select resource type drop-down box:

3. I can now enter the tag key of Name with an optional tag value of PackT:

4. Once this information is entered, I select View query results, and the following is displayed showing two instances that match the key of Name and the key value of PackT.
5. When I am happy with the returned results, I can select Save query as group using the orange button on the bottom right.

This will then ask me for additional details, such as a Group name, a Group description, and, optionally, Group tags:

6. When I have added the required information, I then need to select Create group.
7. This will then display a confirmation message that the group is created:

One of the benefits of having these resource groups configured is that it allows you to perform configuration changes on multiple instances at once through a single command within Systems Manager.