Step one:
Go to genesis settings and make the display of content archives “Entry excerpts” as follows

Step Two:
Copy the code below and paste it to functions.php of genesis child theme
//READ MORE BUTTON
/* Append ellipses to excerpts and then show "Read More" button for manual & automatic excerpts.
* @param type $text
* @return string
*/
function custom_excerpt($text) {
// $text= substr_replace($text,"...",strpos($text, "</p>"),0);
$excerpt = $text . '<a href="' . get_permalink() . '"><button class="read-more-btn" type="button" value="read_more">Read More</button></a>';
return $excerpt;
}
add_filter('the_excerpt', 'custom_excerpt');
/* User defined excerpt length.
* @param type $length
* @return int
*/
function custom_excerpt_length($length) {
return 65;
}
add_filter('excerpt_length', 'custom_excerpt_length');