Ticket Confusion

Apologies for beating a dead horse, I see lots of people have been asking similar questions, but I am a little confused about tickets for upcoming home games.

I live abroad and have done for the last ten years but I am desperate to go to the Forest game after Christmas and take my son for the first (and last) time to Goodison (ideally my Dad as well).

Anyway I had trouble navigating the website, the option to show availability for tickets was there, then a message came up saying there were no tickets available for my membership 'yet' and then when I clicked for the 'event information' it instead then took me to the guided tour event information...

So I emailed them and they told me it was sold-out.

My two questions were; how do I know what type of membership I have? I have a membership from years ago (maybe fifteen or more) and I can still login but there's not much info on the profile page?

And how do resale tickets work? Stubhub has what I need and I can live with the outrageous price... but my biggest fear is being turned away for some reason with my son there. I don't think I could handle that kind of disappointment...

Any advice?