import.ps1

install-module Microsoft.Graph.Users, Microsoft.Graph.Identity.SignIns, Microsoft.Graph.Groups
Connect-MgGraph -Scopes 'User.ReadWrite.All', 'GroupMember.ReadWrite.All', 'Group.ReadWrite.All'

$groupId = "c259b03c-6b11-44ea-a768-76b077d2cb93"

$invite = [PSCustomObject]@{
    mail = "[email protected]"
    name = "Franta Novák"
}

$invitations = Import-Csv -Path "uzivatele.csv" -Delimiter ";" -Encoding UTF8
foreach($invite in $invitations) {
    $mail = $invite.mail

    $user = Get-MgUser -Filter "startsWith(mail, '$mail')"
    if($user) {
        "[$mail] user exists -> adding to group"
        New-MgGroupMember -GroupId $groupId -DirectoryObjectId $user.Id
    } else {
        "[$mail] not exists -> create"
        $guest = New-MgInvitation -InvitedUserDisplayName $invite.name -InvitedUserEmailAddress $mail -InviteRedirectUrl "https://myapplications.microsoft.com" -SendInvitationMessage:$false
        if($guest) { #.Status -eq "PendingAcceptance") {
            "[$mail] add to group"
            New-MgGroupMember -GroupId $groupId -DirectoryObjectId $guest.InvitedUser.Id
        }
    }
}