In this sentence Does “like” mean that it says something in the way you said or it says something like thing you said before?
It could have either meaning.
"It says something on the wall" probably means something written on the wall, so "A like B" is probably answering what? and not how?. That probability is around 60%.
If the second object of says was a person and not a thing, it'd more likely be how?. But only slightly more likely.
Only context could tell for sure.
To rewrite to tell the difference, you can do this:
It says something on the wall, something you said to me before.
It says something on the wall, you said it that way to me before.