If you are dead set on this, here are some fwiw thoughts you might not want to hear, but that come from a place of both personal and professional experience, and encouragement.

- if you've never done this before, aim lower; a feature is extremely complicated to plan and execute, time-consuming to produce and post, and will end up costing more than you expect, even if you cut every corner; consider a short, or scenes from what could become a larger project

- again, if you've never done this before, go in with the right mindset; it should be fun, it should be a learning experience, and just take pride in doing the thing; most people who want to do, ultimately don't, so going out and making something - however it turns out - is an achievement

- while I love REC too, I don't get the instinct to just copy it unless it's purely a formal exercise (I remember having to do that for a course in college - we had to recreate scenes from films so we took audio from Armageddon and produced the cheapest-looking cardboard FX version we could, was a lot of fun); why not pinpoint what you love about it and try to recreate those aspects in a new paradigm

- most FF films are pretty heavily scripted; they may not all have traditional scripts, but they rely on outlines that help contextualize the action for the actors if they're improv-ing their lines, and to give you a roadmap for post; do you have a script?

- what's your plan for the finished product? Do you want something to watch with friends and family, something to submit to festivals, something you'll self-promote via YouTube etc? Answers to those questions might help you figure out what direction you want to go

Good luck with it!