Honestly if you don't know much about computers dont spend so much on one. Ultimately if something breaks you won't be able to sort it and won't be able to replace it from spending all your money.
Honestly either buy something cheaper with like a gtx 1050ti and you'll be happy with it or buy a gaming laptop for a similar price you'll probably in each case not notice much difference or will enjoy the far smoother end user experience of the laptop and a far more recognisable brand like razer to contact if it breaks.
Gaming laptops are more expensive but at this sort of ultra high end range the extra cost of portability is dwarfed by just how expensive the components are anyway.
Can never be too good a pc my first ever pc had a 7.85 gb hard drive it was said the space on that disc at the time would never be filled as hard as u tried now we have tb hard drives ok thers like 20 years since my first pc but at the rate technology progresses ur forces to upgrade every 5 to 10 years
it's very powerful. you will need a high end monitor (4k, high refresh rate, ultrawide) to be able to fully utilize it's strength.
the downside to a system like this is that it's difficult to upgrade. may be incompatible with future graphics cards.
can non Australians answer this question: do you have stores that sell prebuilt pcs with off the shelf parts without much markup?
I hear good things about the corsair one in terms of prebuilts. Just keep in mind it's a unique form factor that could be difficult or impossible to upgrade in the future.