Hi there, totally empathise with your situation my husband is Australian and we've done the trip every other year.
We travelled with our 10mth old and toddler couple of years ago.
In answer to your questions:
Yes you can take pouches of food and formula - ready mixed formula in cartons (this is best as you can't guarantee freshly boiled water on the plane. Take plenty of bottles, if you're having a stop over you can wash and sterilise them- take Milton tablet sterilising travel bags (fill them in hotel bath/sink overnight)
Calpol is also allowed on flight.
Try and time it so you offer a feed on take off which will help with ears pressure and you could also give Calpol in advance. Dummy if your baby uses them? I actually reintroduced a dummy at 10mth specifically for the 24hr flight having ditched it at 3mths- was a saviour.
Pack teething granules too.
Pack a bag of spare outfits for baby but place each full outfit inside a plastic bag - so if there's a vomit or accident you can just grab a carrier bag and then stuff dirty things inside it once changed.
Pack yourself a spare outfit like this too (hubby got vomited on twice on flight!)
when it comes to entertainment- try and pack small new things in separate net bags get one out each hour. Small happyland figures, stacking cups, cloth books, chewing toys, an old purse/wallet filled with things they can pull out, equally empty cup and spoon, toothbrush from meal service.
Take a sling and walk the aisles to soothe or distract - toilets are handy to shut yourself in during a scream fest
Packs of heavy duty silicone ear plugs (bio ears mega pack) to hand out to nearby passengers if things get noisy. We also apologised in advance to nearby fellow passengers saying it was our baby's first flight.
Sleep when baby sleeps - tempting to watch movie but you pay for it later.
We find having a stopover to sleep and break up the flight really helps
Don't worry too much about jet lag it's going to happen no matter how much you try and steer things. Make sure first nap of the day is short a long lunch one - lots of daylight and fresh air on arrival and don't be afraid to offer feeds at night waking to help sleep return (but also their bodies think it's lunchtime at 2am!)
Takes 2weeks to adjust to the jetlad so depending how long you're there it'll be 10days to get in sync.
I hope this helps - happy to chat if you want to discuss further? It's not as bad as everyone makes out xxx