easy
I live in water If you cut my head I'm at your door, If you cut my tail I'm fruit, If you cut both I'm with you What am I?
Common Wrong Answers
“Fish”
A fish lives in water, but it doesn't fit the clues about having a head and tail that change its meaning when cut.
“Seaweed”
Seaweed lives in water, but it doesn't have a head or tail that can be cut to create other meanings or references.
“Shell”
A shell might be found in water and can have a 'head' and 'tail', but it doesn't directly relate to the clues about being at your door or being fruit.