On Vercel, with a cloud provider or on a classic server with Node.js. We choose based on your budget and constraints.
Yes, Vue 2 is no longer maintained. Migration to Vue 3 is usually done in stages, after auditing the libraries in use.
Not all at once. Migration is usually done screen by screen, with the old and new versions coexisting during the work.
Yes, it protects by default against the most common attacks (injections, cross-site request forgery). Regular updates remain essential.
Yes, eventually: this version no longer receives fixes. A gradual upgrade is usually possible without rewriting everything.
Yes, it runs services used by millions of people. Reliability mainly depends on code quality, tests and monitoring.