Booting into Tails Offline
- Plug in your Tails OS USB. 
- Boot into the Tails USB. 
- Select “Yes” for more options. 
- Select “Forward”. 
- Select “Disable All Networking …” (no need to fill in any password). 
- Start Tails. 
Note: Tails OS can be booted into for online use as well. Many users use Tails for privacy oriented browsing and file handling.