In apps with different Roles and permissions you may need to get information about AD Groups. Here are some snippets which can help you with this part of the task.

Get info about current user in PowerShell

get-aduser -Identity $env:USERNAME

Get AD Groups for current user in PowerShell

Get-ADPrincipalGroupMembership $env:USERNAME | select name

Get the wide information list of Users of the AD Group

If you want to get not only user full name, you can use this command:

Get-ADGroupMember -Identity 'g_sp_region_zentrale_admin' | Get-ADUser -Properties DisplayName,EmailAddress | Select Name,DisplayName,EmailAddress,SAMAccountName

It gets more data with the sequence of the requests.

Get AD Groups for a user in .Net (C#)

using System.DirectoryServices.AccountManagement;
// ...
using (PrincipalContext pc = new PrincipalContext(ContextType.Domain))
{
    UserPrincipal? domainuser = UserPrincipal.FindByIdentity(pc, IdentityType.SamAccountName, userLogin);
    if (domainuser == null)
    {
        Console.WriteLine("Error. No user found");
    }
    if (domainuser != null)
    {
        List<string> groups = domainuser.GetGroups().Select(x => x.Name).ToList();
        string userDomainGroups = String.Join(", ", groups.ToArray());
        Console.WriteLine(userDomainGroups);
    }
}

If you use the C# code for SharePoint solution, don't forget to execute it with RunWithElevatedPrivileges()

    SPSecurity.RunWithElevatedPrivileges(delegate ()
                {
            ...
                });