Here "walked in the ways" is an idiom that means he followed Ahab's example. See how you translated this in [2 Chronicles 20:32](../20/32.md). Alternate translation: "He also followed the example" (See: [[rc://en/ta/man/jit/figs-idiom]])
The word "house" is a metonym for the family that lives in the house. In this case it refers to the descendants of Ahab. See how you translated this in [2 Chronicles 21:6](../21/06.md). Alternate translation: "the descendants of Ahab" (See: [[rc://en/ta/man/jit/figs-metonymy]])