I don't want to have to pay for a minecraft account because I'm tied of having to play on my cousins account! Is there a way?

No. Any way you see online, unless is it a legitimate key giveaway (they never happen for Minecraft) is fake.

Your reasoning is the exact reason why you should buy your own account.

$30 is too expensive for you?

Sure. Stop playing Minecraft altogether.

Costs $0, and doesn't require you to use your cousin's account.