I’m having issues with the updater on Nextcloud version 10.0.1, I have: This server has no working Internet connection. This means that some of the features like mounting external storage, notifications about updates or installation of third-party apps will not work. Accessing files remotely and sending of notification emails might not work, either. We suggest to enable Internet connection for this server if you want to have all features.
Is there a way to update it through putty or on Freenas shell?
There have been update questions regarding FreeNAS before (Nextcloud in freenas PHP5.5 update issues). The main question is if you have used an app of FreeNAS in the first place, then it would be better to ask the maintainer to upgrade it.
If it is a separate setup, you should be able to use the Nextcloud updater or the manual upgrade procedure.