Average rating of a twelve year old boy...

I was 12 a few months ago......

In accuracy, this is hard to answer. It sounds plausible to calculate, but it is far tougher in practice. Even the number of chess players in the world is highly debated; to specify an age (like 12) is even trickier. The odd thing with chess is the many false perceptions: like chess is only for "smart people" or GMs are old guys (a lot of GMs are perhaps in 20s through 40s, not old timers like in the movies). Chess takes many years to become really good at (usually), but the age of chess prodigies are getting younger. Some 12 year olds have more experience than senior citizens in chess! 

I would compare your rating, in general, to everyone else (regardless of age) and then note: "oh by the way, I am also 12 and have years of improving/potential to show."

Even average ratings, for any level, are controversial. I think chess.com average rating is 1000 (Glicko, the improved version of elo), but primarily due to closed/abandoned accounts. If you want chess.com percentile, it is under your stats in your profile - but remember it is likely inflated for the reason mentioned above.

Calculating rating average for a specific age is ironically really difficult to accurately measure.

Average definitely not 1400 in otb, no doubt. As for me, I still have 5 or so months to break in to the top 100 list, as a 1760 player probably going to make it

But that is clearly nothing compared to a nine year old who has rating of 2000+++, I know how he did it since I played him over the board twice (At least I got a point off him in 2014, but I don't remember the game, he was 600 back then and I was 400. I lost to him in 2016, and he ran away with rating and I didn't play him again) However, the method I would say is not exactly the best, and not the way Soviets trained. I would trust USSR on anything chess related, not the USA. The Russian/Soviet way is much healthier, it produces Tals and Smyslovs and Botvinniks. I am posting this because the last time he checked his account was in May 2017. However, it is too late for me to apply and Russian/Soviet or the very bad American way, since I cannot use a T Melinvus on myself and reverse age.

1. null

2. 600-1000 otb

3. 2200+, you can see here: http://www.uschess.org/component/option,com_top_players/Itemid,371?op=list&month=1805&f=usa&l=R:Top%20Age%2012.&h=Top%20Age%2012

What is the average amount of enjoyment and learning that a 12 year old gets from playing chess?

It seems like it might not be that healthy to compare the ratings.

Most twelve year olds get nearly no enjoyment nowadays. Especially in the top 100, they feel that if they stop playing they will lose there spot in the list. I make sure that I don't get caught up like that, if I feel no enjoyment I will IMMEDIATLY quit, never show up again.

FIDE? I don't yet have fide rating because our country is big enough for its own chess federation. Is there a Vatican Chess Federation or is it part of the Italian one?

1200 IS THE RIGHT RATING.

I think Bobby Fischer was about 1750 when he was 13.  

Fischer was a grandmaster at 13!

I think the average at 12 years old is 1250

If you go to a really big youth tournament, for example the SuperNationals V, you will see 12 year olds from unrated to 2200+. The average I would think is around 750.

I am 12 and i am around 1600

I'm almost 12 and my rating is around 1200

but I bet bots with the 1600 rating 2 of 3 times

im 12 and beat Antonio bot without help

I'm still not 12,lol