[jcollins]

remove black mold

[karostay]

Pump sprayer mixture bleach water spray let set then pressure wash

[villagetinker]

Originally Posted by jcollins

remove black mold

You do not state where the mold is located. If this is on a wall (drywall), you need to find the reason for the mold first, leaking pipe, crack in stucco, roof leak, errant sprinkler, etc. Then you may need to remove the section of wall and replace, depending to the extent of the damage.
If this is in the shower or bath room (grout?) there are suitable cleaners, and then the grout can be sealed (IF the moisture is coming from the room). Once again, you should determine the source of the moisture.
Hope this helps.