You really wouldn't want to see ancient Greece, Egypt, bring home some artefacts from the jurassic period, but waste this to go back 5 years and buy bitcoins. You could just invest in Apple in the 80's...
Why go back to just 30 years, when you have the capability to go back millions of years? Here is my plan. I will purchase a few AK-47s and a few thousand rounds of ammunition. Then I will travel back 2,000 years to some Latin American nation. I will become the chief of some small tribe, and using my firearms and knowledge of technology, I will conquer the entire world in less than two decades.
Since you're completely new to this you'd end up lost in the jungle or bitten by poisonous snake or spider, catch a fever, whatever and die carrying your AK's before reaching any village.
Even if you managed to do it and present your power by shooting someone you'd be worshipped at first and then assassinated in your sleep or poisoned by some other power hungry warrior. Also in the jungle you wouldn't stand a chance against a tribal warrior with poisoned arrows and blow darts, because he could hear and smell you from afar and you wouldn't even know where to aim your weapon.
It's funny how many people would kill themselves (just like you) when given a time machine.