In this article I will skip the Symfony authentication process as this can be found in the official documentation (it’s more about presenting the solutions in case of using Vue.js):
JWT Token-based Authentication — Does It Have to Be This Way?
Vue.js allows us to either create a SPA (Single-Page Application) or to be used in the form of hybrid where we can inject the components into already existing code or use Vue.js as an extension of current frontend code (In which case I learned the hard way that it can become very messy — You can find more here) — as for both cases the authentication can be implemented/solved in different ways.