If you just want to add a single image that is of the full width, then you can directly upload that on the code in the file src\components\Mobile\Home\RestaurantList\index.js
With something like this inside the restaurants.map function (loop)
<div>
{index ===
5 - 1 && (
<img src="my-image-url" alt="my-img" className="img-fluid"></img>
)}
</div>
(With the above code, change 5 to the position of the restaurant after which your image will appear, and also replace my-image-url
with a valid URL of an image)
===
If you need to customize the current Promo Slider, then first you will need to modify the AdminController.php file present in app\Http\Controllers\AdminController.php
In this file find the updateSlide
function and change the resize value of the image.
Here you can see it is set to 384x384 (square image), you will need to make it a rectangular image like 470x210
Then when you upload slider images, they will be resized to rectangular dimensions.
Now on the customer application, with some Custom CSS magic, you should be able to make it work.