>>8048904You CAN punch the pieces out by hand, but this will lead to an ugly, jagged build that will get you ridiculed anywhere you might post it online. You'll want to buy a pair of nippers. Good starter brands are Tamiya and Xuron, you can find them on Amazon. If you absolutely must get started right now, find a pair of nail clippers. They're not nearly as good as nippers, but they're much better than using your bare hands to twist pieces off the sprue.
Just wedge the nail clipper in there and snip the connection points, then ideally use an xacto blade to clean up any remaining bits of sprue on the part.