Problems with web app -> new to web development

Hello to everyone!
I’m relatively new to web programming and Elixir/Phoenix.

I’m trying to learn wen development using real world examples like this:
https://github.com/cerclecrm/cercle?source=post_page---------------------------

I think I have really trivial problem, but unfortunately I don’t know how to solve it.

In a description how to run an application locally I have this kind of instructions:

-You need to setup a postgresql DB version 9.5
-Rename the file dev.secret_example.exs to dev.secret.exs
-Fill out the parameters of dev.secret.exs
-mix ecto.create (Create the DB)
-mix ecto.migrate (Run the migration)
-mix phoenix.server (You’re good to go!)

The problem is after I’ve renamed dev.secret_example.exs to dev.secret.exs
I don’t know how to “Fill out the parameters of dev.secret.exs”…

I know how to change user name and password for PostgreSQL ONLY…

That’s the code that I have:
use Mix.Config

In this file, we keep production configuration that

you likely want to automate and keep it away from

your version control system.

Configure your database

config :cercleApi, CercleApi.Repo,
adapter: Ecto.Adapters.Postgres,
username: “postgres”,
password: “postgres”,
database: “cercle”,
hostname: “localhost???”,
pool_size: 10

config :arc,
bucket: “YOUR_AWS_BUCKET???”,
virtual_host: true

config :ex_aws,
access_key_id: “YOUR_KEY_ID???”,
secret_access_key: “YOUR_SECRET_KEY???”,
region: “YOUR_REGION??? Israel???”

config :cercleApi, basic_auth: [
username: “admin???”,
password: “admin???”,
realm: “Admin Area???”
]

config :mailman,
relay: “smtp.postmarkapp.com”,
port: 587,
username: “SMTP_LOGIN???”,
password: “SMTP_PASSWORD???”,
tls: :always

all the ??? is something I don’t know what to do…

I’m asking for help,
Thanks!