You can access all of your iClone 6 - and even 5, content directly from within iClone 7 without having to move/copy anything.
In the Content Manager panel click on the "Package" icon and then on the "Custom" tab - see Screen grab below. This will show a "Folder" containing all of your content saved in your iClone 6 "Template" Folder - it does not show any content stored in your iClone 6 "Custom" Folders. The "Folder" and the underlying Folders are all just links to your iClone 6 Template Folder - nothing has been copied or moved on your system. In order to have access to all of your iClone 6 Resource Pack and purchased content you need to keep iClone 6 installed.

If you wish to use your Custom content then you will need to copy or move all of it to your iClone 7 Custom Folder.
If you don't wish to keep iClone 6 on your system you can just select Copy and Paste to get everything from one version to the next. A lot of items in iClone 7 have the same names as those in iClone 6 but may have been updated for the new version. If doing a Copy & Paste, or Move, make sure that you do not overwrite items with the same names in the Folders.
Gerry
System: Win 10 Pro (21H2), Asus X99-E WS, CPU i7-5930K -3,5 GHz, 32 GB DDR4 2666-16 RAM, NVidia GTX 1080 Ti GPU - 11 GB VRAM(Driver Studio-536.99), Samsung 850 Pro 512 GB SSD, 6 TB HD storage.