First of all, delete posts, pages and images that already exist
Check that Fusion core, Fusion builder, contact form 7 are installed and activated.
Check your system status. Click on “Avada” and then click on system status. If something appears in red, fix it before going forward.
Click on Avada and click on demo
Then, You can preview demos from here. Once you are satisfied about one theme, click on import.
Check if the necessary plugins are “ACTIVE”. Then, I advise to tick “all”. Afterwards, you will be able to delete unnecessary content.