How to use instance ephemeral NVMe disk on r6id.2xlarge as the Root device with terraform aws_instance? Root device means the disk where the OS and boot block is installed.

Does the code below automatically use the instance ephemeral disk as the root block device and allocate all the available storage space without root_block_device block?

resource "aws_instance" "web" {
  ami           = data.aws_ami.ubuntu.id
  instance_type = "r6id.2xlarge"
}