Can I back up both to iCloud and my pc using iTunes

While you can certainly backup to both places if that's your preference, you cannot backup to iCloud through iTunes on your Mac or PC. This is not, nor has it ever been a feature. iCloud backups can only be performed directly from your iOS device to iCloud and are done so automatically when enabled, or can be manually started in Settings>Your Name>iCloud>iCloud Backup.

Yes, although when iCloud backups are enabled, you will have to manually start the backup to your computer in iTunes.