Remove the bearing hub. Here you have to pull the large ball bearing off of the axle housing. These things can be anywhere from finger tight to needing a gear puller for removal. Most slide hammer kits come with an axle puller that will make short work of this job. Do not pry against the brake shoes or the brake backing plate.

Notice a bit of the paper gasket remaining around the lower left stud. This gasket must be completely removed and the mating surfaces cleaned before reinstalling the half shaft with new gasket and o-ring. If anything is left in this joint at reassembly it may not close squarely, and it may work loose and leak later.