start by making the controller:

$ bin/rails generate controller Usage: rails generate controller NAME [action action] [options]

... ...

Description: ...

 To create a controller within a module, specify the controller name as a path like 'parent_module/controller_name'.

 ...

Example: rails generate controller CreditCards open debit credit close

 Credit card controller with URLs like /credit_cards/debit -> /credit_cards/credit -> /credit_cards/close
 (If you don't specify actions it creates default CRUD actions (Ex. Create, update, delete, index -> you can google these)
 It will create:
     Controller: app/controllers/credit_cards_controller.rb
     Test:       test/controllers/credit_cards_controller_test.rb
 You will want to create (Possibly)
     Views:      app/views/credit_cards/debit.html.erb [...]
     Helper:     app/helpers/credit_cards_helper.rb

Generate your model: your DB is generated off of the model. Your db keys are generated based off of active record associations (has_many etc: http://guides.rubyonrails.org/association_basics.html)

$ bin/rails generate model Usage: rails generate model NAME [field[:type][:index] field[:type][:index]] [options]

ex. bin/rails generate model CreditCard type:String name:string number:integer etc:etc

...

Active Record options: [--migration] # Indicates when to generate migration # Default: true

...

Description: Create rails files for model generator.

After creating your model, you need to run the db changes:

$ bin/rake db:migrate

Make sure your routes are set up properly

Implement whatever actions you created for your controller ex. def credit // debit code here, anything you want to use on html page use @variableName end def debit // credit code here, anything you want to use on html page use @variableName end def close // close account code here, anything you want to use on html page use @variableName end