[Aetae]

В качестве шутки, css-only.)

<style>
input[name="radio"], p{
    display: none
}
input[name="radio"]:checked + p{
    display: block
}
</style>
<input type="radio" name="radio" id="radio1" checked>
<p>
    <label for="radio2">вперёд</label>
    <br>p1
</p>
<input type="radio" name="radio" id="radio2">
<p>
    <label for="radio1">назад</label> | 
    <label for="radio3">вперёд</label>
    <br>p2
</p>
<input type="radio" name="radio" id="radio3">
<p>
    <label for="radio2">назад</label>
    <br>p3
</p>