how to get a server

You'll probably want to start at the Launch Instance wizard in the EC2 console.

From there, select an Amazon Machine Image and select Arm in the architecture dropdown (required for the t4g family). You can then select the t4g.large instance type in the dropdown below. Below that is a section to configure the amount and type of storage you want.

Additional guidance can be found here: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-launch-instance-wizard.html