For the Barbell Deadlift, start by setting up the bar on the floor with a single weight plate on each side so you can practice some warm-ups and get used to the movement.
From here, it's important to know that the deadlift is a multi-phase movement consisting of a hip hinge and a leg press in one. A hip hinge is much like an Romanian Deadlift and a leg press is much like a squat or just a simple leg press.
Start by lowering yourself to the bar and assuming either a pronated grip (overhand grip) or a mixed grip which is one hand over and one hand under. You can also do a hook grip which is where you tuck your thumb under your fingers and grip the bar.
Next, pull your shoulder blades back and down creating a stable and locked in torso for the first part of movement. Leg press the weight up towards the knee height making sure that your back stays level, your abdominals are strong, and then you're going to squeeze through the glutes to stand up nice and tall pulling the weight up to your hips.
Make sure that you do keep the bar nice and close the whole time after squeezing the glutes at the top lower back.
Now, lower down to the starting position to reset as needed and repeat for the given reps.