Error: Missing required argument in Terraform script

I want to execute remote commands on Ubuntu server using:

resource "aws_instance" "server" {

  # Establishes connection to be used by all
  # generic remote provisioners (i.e. file/remote-exec)
  connection {
    type     = "ssh"
    user     = "openshift"
    password = "qwerty"
    host     = "192.168.1.149"
  }

  provisioner "remote-exec" {
    inline = [
      "ifconfig",
    ]
  }
}

Execution output:

C:\ter>terraform -version
Terraform v1.3.0
on windows_386
+ provider registry.terraform.io/hashicorp/aws v4.31.0

C:\ter>terraform plan
╷
│ Error: Missing required argument
│
│   with aws_instance.server,
│   on main.tf line 1, in resource "aws_instance" "server":
│    1: resource "aws_instance" "server" {
│
│ "launch_template": one of `ami,instance_type,launch_template` must be specified
╵
╷
│ Error: Missing required argument
│
│   with aws_instance.server,
│   on main.tf line 1, in resource "aws_instance" "server":
│    1: resource "aws_instance" "server" {
│
│ "ami": one of `ami,launch_template` must be specified
╵
╷
│ Error: Missing required argument
│
│   with aws_instance.server,
│   on main.tf line 1, in resource "aws_instance" "server":
│    1: resource "aws_instance" "server" {
│
│ "instance_type": one of `instance_type,launch_template` must be specified
╵

C:\ter>

I don't use AWS. I want to execute the commands on a remote Ubuntu server. Do you know how I can fix this?