/ Poles invaded the wrong Anglo-Saxon country
In Australia the wages are much higher then in Europe because the cost of living is much higher, it is all relative.
If you are making $20 an hour in Australia that is considered a low wage. It will not be enough to properly pay off a mortgage and look after yourself and a house/apartment + car etc. Do not move to Australia if you think you will get paid more and have a better standard of living. The taxes are incredibly high and the cost of living is incredibly high. The country is not perfect at all and you will find yourself hard pressed to make a decent living if you do not already have fluent english, career experience in your chosen field etc. Think about it before moving.
The country is nice, the weather is usually good (depending on where you go) and the people are generally friendly. In terms of Australian culture - there isn't one. It is a hotch-potch of many different nationalities. We celebrate Christmas, but you won't see the streets light up like New York or Paris. The fruit and vegetables are good quality and the roads are overall not bad. The standard of living in the middle class is decent and the private schools are generally decent (public schools, many of them, are not great at all). Private schools do get expensive though (upwards of $30,000 a year for some per student). The universities are generally good but they are also very expensive and very bureaucratic (as most are - but especially bad here). There is tall-poppy syndrom here in the media and in the business world, once you achieve good amounts of success you are cut down by many people around you. For example, say you earn over $100,000 per year here in Australia, you will be taxed $17,547 plus 37c for each $1 over $80,000 + 1.5% medicare levy. Australia is a nice place to live if you have a stable income and don't mind crap politicians. Moving from a low wage job in Poland to Australia will be very hard for you to make any kind of decent living, so plan and think first.