Back button fails to implement when using multiple pages in OnsenUI

Hello
I am using Monaca's app production platform.
My JS framework is OnsenUI V2 JS Minimum.
In OnsenUI, we set up multiple pages and create a system that erases and returns the page to the destination like an x.Specifically, I would like to be able to return to the mother index.html like index.html→page1.html→index.html.
I actually incorporated the following code into page1.html, but the button did not appear either.The reference site is http://matorel.com/archives/754.The design of the buttons on the site seemed to be from an external website, so I tried the personally prepared image instead, but it didn't reflect either.
Is there any other cause?As I am still not familiar with Onsen and I am in the process of learning, I look forward to hearing from you about this issue and other content.
Thank you for your cooperation.

HTML

<ons-page>
<ons-toolbar>
    <div class="left">
                <ons-toolbar-button>
                    <ons-icon="ion-close-round" fixed-width="false" style="font-size:60px;vertical-align:-4px"></ons-icon>
                </ons-toolbar-button>
            </div>
</ons-toolbar>    
</ons-page>