If it were possible to use the same USB stick with another operating system, for example to store files to use on Windows, a virus in the other operating system could corrupt your Tails.
To store files in your Tails USB stick, use the [[Persistent Storage|doc/persistent_storage]]. To exchange files between Tails and another operating system, use a separate USB stick.
This is not possible using the recommended installation methods. Tails is designed to be a live system running from a removable media: USB stick or DVD.
No. Those installation methods are unsupported. They might not work at all, or worse: they might seem to work, but produce a USB stick that does *not* behave like Tails should. Follow the [[download and installation documentation|install]] instead.
Our team sometimes publishes emergency releases, whenever important security upgrades are available in Debian or *Tor Browser* before the next scheduled release.