How can I find out when an Editor intends to publish my paper?
Typically, a publisher uses an online system that allows authors to track the status of their paper. Double-check your inbox (particularly Spam folder) for a automatic email from such system (search the journal name for example).

If you are sure that you did not hear from the publisher and the journal editor within 6 months, I would say, it becomes worrying. The academic publishing was never a particularly fast process, but this situation probably oversteps the limits. Consider writing to the support team of your publisher and to Editor-in-Chief of your journal with inquiry. Also, consider sharing the name of the journal with your peers to prevent future misuse of anyone's precious time.