A stair-step crack almost always means that your home’s foundation is sinking more on one side than on the other. That’s because of the building structure of block foundations, which can be a benefit or a detriment depending on the surroundings.
Block foundations tend to get stair-step cracks when the home foundation is sinking more on one side because that sinking process puts substantially more pressure on one side than the other. You can’t fix this one on your own. You need to call in a foundation repair contractor to fix the base problem, rather than just trying to paint over the cracks