Please make sure to use the image of the below sizes with Builders Landing Page free WordPress theme.

Homepage Banner Section: 1920 X 899 px

Homepage About Section: 360 X 278 px

Homepage Testimonial Section: 98 X 98 px

Single Post page with sidebar: 847 X 470 px

Single Post Page without sidebar: 1170 X 470 px

We recommend you to use Regenerate Thumbnails plugin to crop all the images if you have already uploaded the Images.