Well, you only need to build front-end app (JS/whatever) and use it to target back-end (PhalconPHP). It's not that difficult to grasp what you need to do. Such systems usually talk over http protocol, even though it could be just TCP as well.
Or you don't know how to make nuxtjs part? Well, that's JS stuff etc, that's why I prefer having front-end devs doing that part, whilst I do the back-end and conception stuff :)
Use phalcon micro to build an api, nuxt to display it.
that is the logic, but I dont know how to do it, I dont know how to force php phalcon api to show nuxtjs file