Errors setting up Ruby development environment: nodejs not found, could not connect to server - node.js

Question

I'm a new developer-in-training attempting to set up my Ruby development environment on a Windows machine using Ubuntu. I'm following the instructions here:
https://gorails.com/setup/windows/10
I've made it to the last few steps of the process, which is where I'm started to get errors:
# Navigate to the C: drive on Windows. Do this every time you open the Linux console.
cd /mnt/c
# Create a code directory at C:\code for your Rails apps to live (You only need to do this once)
mkdir -p code
#### If you want to use Postgres
# Note that this will expect a postgres user with the same username
# as your app, you may need to edit config/database.yml to match the
# user you created earlier
rails new myapp -d postgresql
#### or if you want to use SQLite (not recommended)
# rails new myapp
#### Or if you want to use MySQL
# rails new myapp -d mysql
# Then, move into the application directory
cd myapp
# If you setup MySQL or Postgres with a username/password, modify the
# config/database.yml file to contain the username/password that you specified
# Create the database
rake db:create
rails server
On the step to set up Postgres:
rails new myapp -d postgresql
I receive this error about setting up nodejs:
/home/event/.rbenv/versions/2.6.5/lib/ruby/gems/2.6.0/gems/railties-6.0.1/lib/rails/app_loader.rb:53: warning: Insecure world writable dir /home/event/.rbenv/versions/2.6.5 in PATH, mode 040777
sh: 1: node: not found
sh: 1: nodejs: not found
Node.js not installed. Please download and install Node.js https://nodejs.org/en/download/
Even after I go to the URL provided and install NodeJS, that error still shows up when I attempt to repeat the process. Is this just a matter of it not existing in the correct path and I need to relocate it?
Also, I've attempted to proceed with the other steps despite that error. When I enter this command, the second last one in the article referenced above:
rake db:create
I receive this error:
could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
Couldn't create 'myapp_development' database. Please check your configuration.
rake aborted!
ActiveRecord::NoDatabaseError: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
Caused by:
PG::ConnectionBad: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
Tasks: TOP => db:create
(See full trace by running task with --trace)
I've searched around about this with little success, and attempted to decipher what the error messages mean; but at my current level of knowledge it just seems beyond me. Appreciate any insight anyone has to share on this!