Try this and place in your functions.php file:
function custom_excerpt_length( $length ) {
return 35;
}
add_filter( ‘excerpt_length’, ‘custom_excerpt_length’, 999 );
function excerpt_more( $more ) {
return sprintf( ‘%2$s’,
get_permalink( get_the_ID() ),
__( ‘Read More’, ‘textdomain’ )
);
}
add_filter( ‘excerpt_more’, ‘excerpt_more’ );