Centering full width and height images on the page

Need help with my starter portfolio template site. I’m having trouble getting some images centered on the page. The full-page project background images on the homepage, and also the header image on the project template page. Below is a read-only link to my site.

https://preview.webflow.com/preview/jacobkeel?utm_medium=preview_link&utm_source=designer&utm_content=jacobkeel&preview=a49f111077b548a8ec81f3e1cc501a21&workflow=preview