Hardwire Dishwasher Installation question
First and foremost follow the instructions included with your dishwasher. It will specify the electrical service required (probably 120V 15A circuit) and will have diagrams on how to make the connections. If you don't have the manual they are commonly available online. Find the model number on the side of the door or door frame.

Connect black to black (hot) and white to white (neutral) wires with an appropriate listed connector (e.g., wire nuts). These connections will sit inside a fire-retardant (usually metal) box built into the base of the dishwasher.

Inside that box you should also see a green or bare Cu wire attached to the box itself or some other means of bonding to the metal frame of the dishwasher (such as a clip or screw). Connect the grounding wire from your circuit to the metal frame here. This is an important safety feature to avoid an electrocution hazard. If you don't see how to make this grounding connection ask a more handy neighbor or hire a handyman to do it.