First job is to get the car safely jacked up off the ground and remove the road wheel, then undo the brake caliper retaining bolts and slide the whole caliper off the disc.
Undo the brake disc retaining screw and remove the brake disc.
Undo the hub nut, a nut gun is best for this as it is difficult to hold the hub still when using a spanner.
Using a puller and bracket pull the hub out of the bearing.
The inner bearing will almost certainly come off with the hub and this will need to be carefully cut off using a grinder.
Undo the four bearing securing bolts ant the bearing should come out, but you may find you need to use a bit more aggressive methods as it will almost certainly have corroded in place.
Once you have removed the wheel bearing clean out the housing so the new bearing fits nicely. Then fit the new wheel bearing using the reverse of the procedure above.