Your website uses the Fusion’s Avada Theme as the base of how it functions. Avada has extensive help documentation and videos on how to set up and update a website which uses their theme.
For a quick start guide on using Avada’s Theme Builder, visit this page: https://theme-fusion.com/documentation/avada/avada-builder/avada-builder-quick-start-guide/
For extensive help documentation of every aspect of the Avada Theme, visit this page: https://theme-fusion.com/documentation/avada/
For an extensive video tutorial library on how to use Avada, visit this page: https://theme-fusion.com/documentation/avada/video-tutorials/