Change credits from function.php

Hello, I’m a graphic designer and I have difficulty with the codes.
I want to find a permanent solution to change the credits of the sites.
I’m currently using this solution with Twenty Fourteen theme:

// MODIFICA COPYRIGHT & AUTOUP-DATE
function my_updated_copyright($first_year, $owner) {
    $copyright_notice = '? ' . $first_year;
    $current_year = date('Y');
    if($first_year != $current_year) {
    $copyright_notice .= ' - ' . $current_year;
    }
    $copyright_notice .= ' ' . $owner;
    return $copyright_notice;
}
function my_custom_credits(){
	echo '<span>'.my_updated_copyright(2016, 'MY NAME CREDITS').'</span>';
}
add_action('twentyfourteen_credits','my_custom_credits');

I would insert a clickable link to the ‘MY NAME CREDITS’ and remove the credits of wordpress.

Can someone help me? Thanks

Gianluca