Two answers.

The title only search. You will need to follow the instructions for using the 3rd party Relevanssi plugin, here:

https://searchandfilter.com/documentation/3rd-party/relevanssi/

You will need to look through the Relevanssi plugin options for what it searches, and whether it searches for whole words etc. I would not recommend the relevance option in your case.

The image to be clickable. Follow these instructions to be able to modify the results.php file:

https://searchandfilter.com/documentation/search-results/using-a-shortcode/#customising-the-results

In the standard results.php, see lines 56-62 (yours may now be different) for the image code:

<?php 
if ( has_post_thumbnail() ) {
  echo '<p>';
  the_post_thumbnail("small");
  echo '</p>';
}
?>

This would need to be changed to:

<?php
if ( has_post_thumbnail() ) { ?>
  <a alt="<?php esc_html(get_the_post_thumbnail_caption());?>" href="<?php the_permalink(); ?>"><?php the_post_thumbnail("medium");?></a>
<?php	} ?>

Notice I changed the image size also. There are many different sizes you can pick. Normally, the smallest is "thumb"