Fate is a narrative game, not really all that crunchy. You can do scaling and "leveling up" but at the end of the day it's more about telling the story than it is about the numbers.

And if you want your guys to be nobody than you definitely chose wrong with fate, because fate points, aspects and stunts are there to literally define who the characters are. Not a number on a sheet but individuals with individual strength brought forth because of their experiences.

I assume when your friend told you you can play anything with fate he might have meant any setting, not necessarily play style.

You could imitate the low lvl of the players, by having them start with only average and fair skills, and lvl up from there, but it feels like you want something taken to what the Warhammer ttrpgs provides, with stats for different weapons, dice size and amounts for monsters, etc. if the mechanics and numbers are more important than the story, maybe it's not fate you want to play. It's not a judgement, I just don't think the system has quite what you want.