You're aiming to match the performance of other people who already have a head start on you (and are therefore better than you at the moment) and are devoting their life to it. lots of sleep, early nights, fanatical diets, no booze, planning everything around training and recovery. What do you need to do to catch up and keep up? The same, but more, and then hope you were blessed with the right genes.
Don't be coached by a bunch of strangers on an internet forum, most of whom don't know their arses from their elbows. Join a good local tri club (or if you can't find a good local one, maybe start with a competitive local cycling club. And swim team. And harriers (not some fat bimblers social running club). Find a coach there, or by word of mouth from the harriers.
realise that statistically speaking, you won't make it. But statistically speaking, playing the lottery is stupid... And millions of people do that. Some of them win it, too