@Yikes1232011101 

I'm not really sure what will be shown as "free space" on the VM, but you will be able to copy a 6GB file to a folder in the user profile (which is redirected by FSLogix to the VHD), but not to a folder outside the user profile (e.g. c:\temp\).

Best practice however is to make sure there is sufficient free space on the VM to allocate the userprofile. Instant clones are thin provisioned and removed when logged off, so unused space won't take any storage.