How would I display both first name and Surname on my html spring boot jdbc

Question

I am using a select statement in my jdbcTemplate. I am trying to select firstname and surname and display them on the html page however I am getting errors.The error code I am getting on the HTml page is "Incorrect column count: expected 1, actual 2"

    public List<String> getAllUserNames() {
    List<String> usernameList = new ArrayList<>();
    usernameList.addAll(jdbcTemplate.queryForList("SELECT FirstName,Surname from paitents",String.class));
    return usernameList;
}

Html file

<tr th:each="user : ${users}">
    <a href="#" th:text="${user} + ${user.Surname}" ></a> <br>
<!--    <td th:text="${user}"> </td> <br>-->

</tr>
</body>