If i have Debian 9 installed on Virtualbox and set to work with Whonix Gateway, and i install Tor browser how secure is to browse internet and connect through ssh to remote servers in comparison of using Whonix Workstation?
Why would you want to do that? Juste use the Workstation instead, it’s based on Debian already (Jessie). If you need 64 bits and/or Stretch, just use the Whonix-14 version.
This creates a Tor over Tor situation. Strongly disapproved of
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links to differences between whonix workstation and others
Whonix 14 is not officially supported yet.
How to use Tor browser then with Debian on Virtualbox?