Well, since the text ‘Download Resume’ is hard-coded inside a theme file you have to override this behavior by making a Child Theme.
After making a Child Theme and activating it you would have two new files namely style.css and functions.php.
In your functions.php put this custom code just below your existing code.
function biography_after_text_slider() {
global $biography_customizer_all_values;
$biography_header_contact_url = $biography_customizer_all_values['biography-header-contact-url'];
$biography_header_resume_url = $biography_customizer_all_values['biography-header-resume-url'];
if( empty( $biography_header_contact_url) && empty ( $biography_header_resume_url ) ){
return;
}
?>
<div class="goest-btn">
<?php
if( !empty( $biography_header_contact_url) ){
?>
<a class="button button-feature button-contact" href="<?php echo esc_url( $biography_header_contact_url ); ?>">
<?php _e( 'Contact Me', 'biography' );?>
</a>
<?php
}
if( !empty( $biography_header_resume_url) ){
?>
<a class="button button-feature button-resume line-btn" href="<?php echo esc_url( $biography_header_resume_url ); ?>">
<?php _e( 'Buy My Book ', 'biography' ); // changing to your custom text?>
</a>
<?php
}
?>
</div>
<?php
}
Please notice in the code above, I have changed the default text to your custom text for button. This should work for you.
Thanks