I'm unsure on how to buy things...

lel, i know it's lazy, but if there's ever a problem, i can withdraw my gainz from a different country.

What do you mean by "not always true"?

It was always true in my case, i bought with a credit card.

Margin trading is borrowing money that you don't own to trade with.
Stick with bitstamp if you only want to buy/sell.

I'm a lux-fag too btw.
Claiming taxes this year is going to be interesting.

Did you claim yourself as self-employed? Do you have to do that when you buy/sell shitcoins?

I didn't claim anything yet.
I held for years and never sold til now.
I only sold and traded this year.

If you actively buy/sell you'll have to claim taxes.
Use bitcoin.tax for that. You can simply import everthing from bitstamp/bittrex.
If you earn less than a certain amount (=?), you don't have to bother claiming anything; it's totally up to you.