Your config.ini to your emulator should look something like below
#To get the camera working visit git.krews.org and download Apollyon from official-plugins!
#Database Configuration.
db.hostname=localhost
db.port=3306
db.database=database name here
db.username=root
db.password=database pass...
it uses php 7.4 ......................... this isnt 2017
https://prnt.sc/ylafvx
Heres your issue; it can't read the file meaning 1. It may not exist at all or 2. you didn't do the properties settings that it said in the tutorial. (https://prnt.sc/ylajdd)
Anyone who can read a simple error...
Did you run the command :update_navigator and/or restarted the emulator? Plus if im not mistaken FluxRP emulator the navigator shouldn't matter as its not useable as a user on the retro/rp.