Botiga supports the core Header Image feature in WordPress. To locate this option, please go to Customize > Header > Header Image.
The recommended image size is 1920×500. Once you upload your image, you will be presented with an option to crop it (you can ignore this option, if you want).
Tip: Considering this will be a large image, it is recommended you optimize it before uploading with a service like https://shortpixel.com/. If you already have a plugin that optimizes images when you upload them, you can ignore this.
Please note: the header image will be displayed on all your website’s pages, right after the header.