How to add new instances in existing resource group in Azure via Terraform?

I would like to add a new VM to existing resource group in Azure which already contains 3 VMs. While running tf apply, it throws an error saying the resource group already exists.

If you want to create a VM in an existing resource group instead of creating a new resource, you can use a data block to import the existing resource group.

Here is the updated Terraform code for creating 3 resources in an existing Resource Group.

    provider  "azurerm"  {
    features  {}
    }
    data "azurerm_resource_group" "example" {
      name = "Existing-RG-Name" 
      }
    
    resource  "azurerm_virtual_network"  "vnet"  {
    name = "venkat-vnet"
    address_space = ["10.0.0.0/16"]
    location = data.azurerm_resource_group.example.location
    resource_group_name = data.azurerm_resource_group.example.name
       }
    resource  "azurerm_subnet"  "subnet"  {
    name = "vm-subnet"
    resource_group_name = data.azurerm_resource_group.example.name
    virtual_network_name = azurerm_virtual_network.vnet.name
    address_prefixes = ["10.0.1.0/24"]
    }
    resource  "azurerm_network_interface"  "samplenic"  {
    name = "VM-nic"
    location = data.azurerm_resource_group.example.location
    resource_group_name = data.azurerm_resource_group.example.name
    ip_configuration  {
    name = "internal"
    subnet_id = azurerm_subnet.subnet.id
    private_ip_address_allocation = "Dynamic"
    }
    }
    resource  "azurerm_windows_virtual_machine"  "myvm"  {
    name = "venkat-vm"
    location = data.azurerm_resource_group.example.location
    resource_group_name = data.azurerm_resource_group.example.name
    network_interface_ids = [azurerm_network_interface.samplenic.id]
    size = "Standard_B1ls"
    admin_username = "Venkat"
    admin_password = "Password1234!"
    os_disk  {
    name = "VM-osdisk"
    caching = "ReadWrite"
    storage_account_type = "Standard_LRS"
    }
    source_image_reference  {
    publisher = "MicrosoftWindowsServer"
    offer = "WindowsServer"
    sku = "2019-Datacenter"
    version = "latest"
    }
    } 

Terraform Apply:

Reference: Data Source: azurerm_resource_group