powershell add users

#Enter a path to your import CSV file
$ADUsers = Get-Content C:\Users\Administrator\Desktop\file.csv

for ($i = 0; $i -lt $ADUsers.Length; $i++)
{
    Write-Output ([string]$ADUsers[$i])
    $firstname = ([string]$ADUsers[$i]).Split(' ')[1]

    $lastname = ([string]$ADUsers[$i]).Split(' ')[2]
    $fullname = "$firstname $lastname"
    $logonname = "$firstname.$lastname"
    $OU = "CN=Users,DC=cosci,DC=be"
    $domain = $env:userdnsdomain
    $Password = "School123"
    $Pass = ConvertTo-SecureString $Password -AsPlainText -Force
    $BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($Pass)
    if (Get-ADUser -F {SamAccountName -eq $logonname})
        {
                #If user does exist, output a warning message
                Write-Warning "A user account $Username has already exist in Active Directory."
        }
    else
    {
        Write-Host "Creating Active Directory user account now" -ForegroundColor:Green

        #Creating user account with the information you inputted.
        New-ADUser -Name $fullname -GivenName $firstname -Surname $lastname -DisplayName $fullname -SamAccountName $logonname -UserPrincipalName $logonname@$Domain -AccountPassword $pass -Enabled $true -Path $OU  -Confirm:$false

    }
}