After you deploy the VM or the EC2 instance for the storage gateway, you would need to complete the Storage Gateway activation. During the activation process, gateway fetches an activation key and associates that with your AWS account. Previously you would provide the IP address, connect to the gateway and activate the gateway through the AWS management console. If you use CLI, you can fetch the key either running a curl request to the gateway IP or from the gateway VM or EC2 console using Option 0: Get Activation Key. Then use this key in the ActivateGateway CLI command.
With the New experience on the Storage Gateway console, now it is possible to pass the activation key through the management console in the Activation steps. You can enable New experience as below in your Storage Gateway console.

Once you enable new experience, you would see the console as below to create gateway if you don’t have any existing gateways. Here, select create gateway.

Next, you would see the following to Choose gateway type. In this example, I am going to choose File gateway and select Next.

In this step, you would select the host platform. In my example, I am using Amazon EC2 and select Next.

At this stage, you would Select the service endpoint. I am using a Public service endpoint and select Next.

So, here comes the new additional feature of providing the activation key in the new console. You can activate the gateway either connecting to gateway providing its IP address or provide the activation key. Using the new method to provide activation key, you don’t need to have TCP port 80 connectivity from your workstation the gateway VM IP address.

You can fetch the activation key from the gateway VM or EC2 local console as below. To fetch the activation key, press 0. If you are running into issues with fetching the activation key, please check this troubleshooting post.

Then, choose the region, network type and endpoint type. After providing the endpoint type, you would get the Activation key below.

You can copy the above activation key and provide as below in the management console under Connect to gateway section and select Next.

In this step, you can activate the gateway providing the gateway time zone, gateway name and any Tags.

After activating the gateway, you would need to assign the local disks as cache storage. Then, configure logging and complete the activation process.

Please comment if you have any questions or feedback.