Amazon web services – How to access EC2 instance using its public IP via curl command? EC2 created via Terraform

I have created an EC2 instance and security group resource via Terraform file. However when I do,

curl  http://<public IP>:8080

I get
curl: (7) Failed to connect to port 8080 after 8 ms: Couldn’t connect to server

Here is the tf file. How to fix this so I can access EC2 instance via the curl command?

provider "aws" {
  region = "ap-southeast-2"
}

variable "server_port"{
  type = number
  description = "the port for HTTP"
  default = 8080
}
resource "aws_instance" "name" {
  ami = "ami-0dfb78957e4edea0c"
  instance_type = "t2.large"
  vpc_security_group_ids = [aws_security_group.instance.id]
  user_data = <<-EOF
              #!/bin/bash
              echo "Hello, World" > index.html
              nohup busybox httpd -f -p {var.server_port} &
              EOF
  
  user_data_replace_on_change = true

  tags={
    Name="terraform-example"
  }
}

resource "aws_security_group" "instance"{
  name="terraform-example-security-instance"
  ingress {
       from_port = var.server_port
    to_port = var.server_port
    protocol = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }
   egress {
    from_port        = 0
    to_port          = 0
    protocol         = "-1"
    cidr_blocks      = ["0.0.0.0/0"]
    ipv6_cidr_blocks = ["::/0"]
  }
  tags={
    Name="terraform-example"
  }
} 

output "public_ip" {
    value = aws_instance.name.public_ip
    description ="The public IP address of EC2"
}