Hello,
Sorry for the delay in answering. Have you installed and activated all the required plugins (Appearance > Install Plugins)? https://xstore.helpscoutdocs.com/article/36-included-plugins
Looks that WPBakery page builder is not installed or activated but you have the code of that plugin on that page and got the fatal error.
Why can’t you install theme via Dashboard? Does your server meet theme requirements, notably upload_max_filesize: 20M, or greater? https://xstore.helpscoutdocs.com/article/60-xstore-theme-requirements
Also, we can help you with theme and version installation if you provide Dashboard and FTP access to your site.
Regards