Hi itsabusamra,

1. About your first issue, you can upload images for mobile. Please follow these steps to fix it:

- Go to Admin - Online Store  - Theme - Customize

- Open section GPS Slideshow - Slide - Mobile image

- Choose image you want to show on mobile

- Click Save to save the updates then check on frontend.

2. Please follow these steps to fix the GPS logo list issue: 

- Go to Admin - Online Store  - Theme - Actions - Edit code 

- Open file from this path: Assets - gps-homepage.scss.liquid

- Scroll to line 1485, you can see this piece of code

- Delete this code marked

- Click Save to save the updates then check on frontend.

3. please follow these steps to centered all of text and the social 

- Go to Admin - Online Store  - Theme - Actions - Edit code 

- Open file from this path: Assets - gps-header-footer.scss.liquid

- Scroll the end of file and add this code like image below

- Here's the code piece:

@media (max-width: 767px) {
  .site-footer{
    .middle-footer{
      .col-12.gp-footer-block{
        .text-wrapper{
          text-align: center !important;
        }
        &> *{
          justify-content: center !important;
          
        }
        .text-column-with-image-wrapper {
          text-align: center!important;
          .image-wrapper img {
            margin: 0 auto;
          }
        }
        .vertical-link-list-wrapper {
          text-align: center!important;
        }
        .newsletter-wrapper {
          .content {
            text-align: center!important;
          }
          .footer-socials-wrapper, form {
            justify-content: center!important;
          }
        }
        .horizontal-link-list-wrapper {
          .title-content {
            text-align: center;
          }
          ul {
            jusity-content: center!important;
          }
        }
      }
    }
  }
}

- Save to save the updates then check on frontend

Be Steven

Best regards