<div>
    姓名:<input id="i1" type="text" name="name">
    年龄:<input id="i2" type="text" name="age">
    性别:<input id="i3" type="radio" name="gender" value="男">男
    <input type="radio" name="gender" value="女">女
    <button type="button" onclick="add()">添加</button>
</div>

<table id="tb">
    <caption>学生信息</caption>
    <tr>
        <th>姓名</th>
        <th>年龄</th>
        <th>性别</th>
        <th>操作</th>
    </tr>
</table>

<script>
    /*添加学生*/
    function add() {
        /*获取姓名*/
        let name = document.getElementById("i1").value;
        /*获取年龄*/
        let age = document.getElementById("i2").value;
        /*获取性别*/
        let gender = document.getElementById("i3").value;

        /*获取table*/
        let table = document.getElementById("tb");

        table.innerHTML += "<tr>" +
            "<td>" + name + "</td>" +
            "<td>" + age + "</td>" +
            "<td>" + gender + "</td>" +
            "<td><a href='javascript:void(0)' onclick='del(this)'>删除</a></td>" +
            "</tr>";
    }

    /*删除学生*/
    function del(o) {
        /*获取table*/
        let table = o.parentElement.parentElement.parentElement;
        /*获取tr元素*/
        let tr = o.parentElement.parentElement;

        /*删除tr,找到table和tr移除就可以了*/
        table.removeChild(tr);
    }
</script>