It is generally considered poor writing practice to use a pronoun outside of quotations to refer to a person mentioned in quotations who hasn’t been introduced yet. This can lead to confusion for the reader, as they may not be able to tell who the pronoun is referring to.

Instead, it is recommended to introduce the person first before using a pronoun to refer to them. For example, you could say:

John said, “I’m going to the store.” In this case, you could follow up with, “John then left to go to the store.”
“I’m going to the store,” said John. In this case, you could follow up with, “He then left to go to the store.”

By introducing the person first, the reader knows who the pronoun is referring to and can follow the conversation more easily.