Here are some ways to use pronouns when talking about a shelter:
* If you've already mentioned the shelter: "The shelter was small, but it was warm." (using "it" to replace "shelter")
* If you're talking about a general concept of shelter: "They needed a place to stay, and they found one." (using "one" to replace "shelter")
* You could use a relative pronoun: "The shelter where they stayed was run by volunteers." (using "where" to refer to "shelter")
Let me know if you have another question!