Adding newly created users to pre-existing groups - powershell

Question

This script currently creates new users after importing data from a CSV file
Import-Module ActiveDirectory
Import-Csv "C:\testcsv.csv" | ForEach-Object {
$userPrincinpal = $_."samAccountName" + "#NWTC.local"
New-ADUser -Name $_.Name `
-Path $_."ParentOU" `
-SamAccountName $_."samAccountName" `
-UserPrincipalName $userPrincinpal `
-AccountPassword (ConvertTo-SecureString "Password1" -AsPlainText -Force) `
-ChangePasswordAtLogon $false `
-Enabled $true
}
This is the csv file I am importing from:
Name,samAccountName,ParentOU,Group
Test Test1,TTest1,"OU=Business,DC=NWTC,DC=local",TestGroup
After a user is created, I want to add them to an already exisiting group. There will be different groups I want different users to be added to, but only 1 group per person.
I've been playing around with Add-AdGroupMember, but I'm not sure how to proceed. Something like this: Add-ADGroupMember -Members $_.Members. This is the first time I'm working with CSVs, so I'm in new territory

Answer 1

New-ADuser does not support this functionality so you will have to do that yourself after the fact. What you could do is have New-ADUser spit out the AD user object it creates and use that with Add-ADGroupMember.
$newUserProperties = #{
Name = $_.Name
Path = $_."ParentOU"
SamAccountName = $_."samAccountName"
UserPrincipalName = $_."samAccountName" + "#NWTC.local"
AccountPassword = (ConvertTo-SecureString "Password1" -AsPlainText -Force)
ChangePasswordAtLogon = $false
Enabled = $true
}
try{
$newADUser = New-ADUser #newUserProperties -PassThru
Add-ADGroupMember -Identity $_.Group -Members $newADUser.SamAccountName
} catch {
Write-Warning "Could not create $($newUserProperties.samaccountname)"
}
The error handling is crude but should exist in some form to account for failures in the source data or misconceptions of existing users. Basically just getting $newADUser and using it for Add-ADGroupMember
We use splatting of the parameters here. That way you don't have to worry about having nice formatted code by using backticks.

Answer 2

Add the Add-ADGroupMember in the ForEach-Object after the new user is created :
Import-Module ActiveDirectory
Import-Csv "C:\testcsv.csv" | ForEach-Object {
$userPrincinpal = $_."samAccountName" + "#NWTC.local"
New-ADUser -Name $_.Name `
-Path $_."ParentOU" `
-SamAccountName $_."samAccountName" `
-UserPrincipalName $userPrincinpal `
-AccountPassword (ConvertTo-SecureString "Password1" -AsPlainText -Force) `
-ChangePasswordAtLogon $false `
-Enabled $true
Add-ADGroupMember -Identity 'AD_GROUP_WHERE_YOU_ADD_MEMBERS' -Members $_.samAccountName
}