The wheel bearings are pressed onto the wheel hub and will require a hydraulic press to remove them from the hub and install the new ones onto the hub.
You will need to remove the steering knuckle which is connected to the car by the upper & lower ball joints. Once the knucke assembly is removed, press out the hub and wheel bearing from the knuckle. The using a bearing splitter, remove the bearing from the hub. Reverse to install. It takes some practice to do this without damaging the new bearing. Watch for c-clips holding the bearing in the knuckle.
I have included a picture for refrence:
#1 is the hub and #3 is the bearing.