The Lagar theme uses the Elementot Theme Builder feature - there are design templates for Single Product, Shop, Product category - so you can have quick and easy complex and fully-customizable designs for your WooCommerce shop pages. Check these guides for detailed instruction:
So, every time that you add a new product it will get the default Single product template:
If you edit this template, from Dashboard > Templates > Theme Builder > Single Product, it will change the layout and design globally, to all the existing and future products.
The Single Product template gets automatically the custom Product Title, Product Short Description, Product data and Featured image of each product:
Click on the Edit with Elementor button in the Content section of the product in order to add its description and edit the fruit-background image:
You can use the Product Info Section saved template to get the same design and structure as here: