Download the theme
Download Theme files from Themeforest by going to the Downloads tab and finding the Bacola Theme.
All files & documentation: It is a product archive with documentation,plugins folder and some additional files like changelog, lisense etc
Installable WordPress file only: It is the archive theme-name.zip with the theme itself -this file you need to install
If you get such an error while you're installing the theme The package could not be installed. The theme is missing the style.css stylesheet. then it is likely you try to install the whole theme files including the documentation and the others. You have to make sure you installed the installable WordPress file only.