✅ Creating new cancellation token from multiple other tokens

public async Task DoSomethingAsync(TimeSpan timeout, CancellationToken cancellationToken)
{
  CancellationTokenSource timeoutCancellationTokenSource = new();
  timeoutCancellationTokenSource.CancelAfter(timeout);

  // Create someCombinedCancellationToken which will cancel if either cancellationToken is cancelled
  // or timeoutCancellationTokenSource is triggered

  await DoSomethingElseAsync(someCombinedCancellationToken);
}

public async Task DoSomethingAsync(TimeSpan timeout, CancellationToken cancellationToken)
{
  CancellationTokenSource timeoutCancellationTokenSource = new();
  timeoutCancellationTokenSource.CancelAfter(timeout);

  Task result = DoSomethingElseAsync(timeoutCancellationTokenSource);
  while(!result.IsCompleted)
  {
    if(cancellationToken.IsCancellationRequested)
    {
      timeoutCancellationTokenSource.Cancel();
    }

    await Task.Delay(100);
  }
}