Hello,
Regarding the folders/files, you will find all files exactly how you see in our preview site. (except for the images/videos that are replaced by placeholders). A few folders that you may remove if you want:
/Ajax: The HTML files in that folder are just examples on how to use Ajax requests for your site.
/CSS: Make sure you keep in folders Demos and Skins just the demo files that you are using.
/Images: Go to Demos folder and remove the demos that you are not using, you can also remove the placeholders images (grey images).
/JS: : Make sure you keep in folders Demos, Views and Examples just the demo files that you are using.
/Master: : Do not upload that folder to your host server, those are just the source codes to generate the template.
/Vendor: That folder is where all the plugins used on Porto are located, make sure to keep only the ones you use and are included in the HTML files.
/Videos: Remove the videos that you are not using.
You can basically check which files you added to the header/footer (js/css) of your site and remove the other ones.
Hope that helps.
Best Regards,
Okler Themes