To update the hero section in Shane Jekyll Theme, open _data/site_data.yml file.
You will find the following code there,

hero:
  profile_name: '<span>Ave</span> Brook<span class="overlay_effect"></span>'
  designation: Independent Web Developer
  profile_img: "/assets/img/slider/1.jpg"

profile_name : for the heading
designation : for the sub heading
profile_img : for the image