This refers to Jesus. Translate as "the Word" if possible. If "Word" is feminine in your language, it could be translated as "the one who is called the Word." See how you translated this in [John 1:1](../01/01.md).
Here "flesh" represents "a person" or "a human being." Alternate translation: "became human" or "became a human being" (See: [[rc://en/ta/man/jit/figs-synecdoche]])
The phrase "the one and only" means that he is unique, that no one else is like him. The phrase "who came from the Father" means that he is the Father's child. Alternate translation: "the unique Son of the Father" or "the only Son of the Father"