How do i display an image on a master template

Hello,

Creating my first Perch site. So pretty new to this. I was wondering how i place images on a master page and have the URL correct on all pages?

i have a master page called inner.php and i want to use it as a top level page, Second level and Third level page. But if i change the URL to match the top level, it doesnt work second and third level.

I am using Quill feather for my CSS and Javascript put i cant seem to create an image one.

my code for that is

    public function get_tel_icon($opts, $index, $count)
    {   
        $out = array();


        $out[] = $this->_single_tag('img', array(
                    'src'=>'/fireplace/images/phone-icon.svg',
                ));


        return implode("\n\t", $out)."\n";
    }