The number of products in slide can be defined by going to Prestashop admin panel >> Billion Themler >> choose the theme >> Theme Settings >> select product slider:
Let us know if you mean anything different.
The options shown on the screenshot will define the number of products in a row for each screen mode (Desktops, Laptops, Tablets, Phones).
So to achieve the view shown on your first screenshot, please set it this way:
Desktops: 2 (for desktops). Same for each responsive mode.
Number of products in slide: 2
This will display products in one line (because 2/2)
If you need for example to display four featured products in one line on Desktops, please set:
Desktops: 4 (number of products in a row)
Number of products in slide: 4
This will display four products in one line.