Hi wesleigh,
to buy apple and shares on international markets you need to get an international brokerage account. There are several online brokerage accounts that you can use. However it is hard to find one that allows foreigners to open an account and also not have to open it in person.
The one I use is www.interactivebrokers.com They came highly recommended. Their platform is quite sophisticated, so it took me some time to figure out how to use it. But it takes a few hours and the basics are fairly straight forward.
Using their platform you can buy shares from most big exchanges in the world. I have bought shares on the NYSE, TSX, TSX-V and I have bought options on the AMEX exchange. All pretty cool. You can also buy CFD's. You can buy bonds too. You can also buy and sell currency very easily and cheaply. If you open an account and you fund it with Dollars, but then want to buy shares of Rolls Royce on the London stock exchange, you will first need to buy pounds using the platform, and then once you have pounds you can buy the shares on the LSE.
It seems daunting at first but it is very cool to be able to buy these international shares!