The subject pronoun that you would use when speaking to a friend is "tú."
When speaking to a friend, you would use the subject pronoun "tú". "Tú" is the informal pronoun used in Spanish when addressing someone of the same age or someone you know well. To determine the correct subject pronoun to use, it is important to consider the level of formality and the relationship with the person you are speaking to. In this case, since you are addressing a friend, the informal pronoun "tú" would be appropriate.
