Sorry, I didn't mean to imply that you personally weren't aware of all the different churches. I'm just concerned about the level of general knowledge of some posters/possible readers on the thread.
I don't honestly have much knowledge of what happens in other Protestant churches. Within the C of E (which is definitely a Protestant church, by the way - not sure why this point was queried by someone earlier!) then I know that FHC was standard in the church I went to when my kids were that age, and also the church my sister attended when her kids were that age (different area of the country, but also C of E). Most of my friends with kids in other areas don't go to church, so I don't really know how standard it is across other C of E churches, but it's definitely a thing.
One thing that strikes me is that when I was growing up, our church (C of E, but in yet another part of the country) didn't have a FHC until we were about 13 and had just been confirmed. It wasn't a separate event at a younger age. I think this was normal back then in the C of E. The idea was that you should have a mature understanding of the significance of communion, and have made your commitment to Christianity after going through the confirmation preparation classes, and THEN you could take communion. But now it's different, and a separate FHC has been introduced for the younger age group, who would need to have gone through some preparation classes but who are too young to be properly confirmed yet. Maybe they changed it because having a special event at a younger age helps to encourage kids to keep coming to church, and the C of E has a demographic problem with ageing congregations! So this may be yet another reason why people's experiences have differed.
No idea what happens in the non-C of E Protestant churches. Let alone the Orthodox churches! It's very hard (and a bit unwise) for me to generalise.