Link to another view using ruby in windows - ruby-on-rails

Question

I am doing a simple CR and trying to put some link/button(add,edit etc), when the user will click the add it will direct to that view..
Question: How should I indicate which view will be load when I click the specific link/button?
Index.html.erb
<h1>My First CRUD!</h1>
<%= link_to "Add Page", posts_path %>
<%= link_to "Edit Page", posts_path %>
<%= link_to "Showx Page", posts_path %>
Posts Controller
class PostsController < ApplicationController
def index
end
def addItem
end
def create
#post = Post.new(post_params)
#post.save
redirect_to #post
end
def show
#post = Post.find(params[:id])
end
private
def post_params
params.require(:post).permit(:item, :description)
end
end
Routes
Rails.application.routes.draw do
# For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
resources :posts
root "posts#index"
resources :posts
root "posts#addItem"

Answer 1

You can declare all the root routes that you want in your routes.rb, but it'll take just the one that was declared first, it doesn't matter if the definition has some mistake, it won't tell you.
And the route where the link_to will redirect is what you declare as second argument (in this case).
In your example you have three link_totags, which are pointing to the same path. If you'd like to make the "Edit" link_toredirect to the posts#edit method you firstly must create the edit method in your posts_controller and then add it to your route as:
get '/posts/edit/:id', to: 'posts#edit'
But in your case as you have resources :posts it makes the whole work for you and creates all the routes defined in the posts#controller, what resources do is to map a number of related requests to actions in a single controller, that's to say;
When Rails application receives a request for:
GET /posts/edit/1
That's what happen when you go to edit the a certain post by passing the id of 1, then it asks the router to map it to a controller action. If the first matching route is:
resources :posts
Then Rails dispatchs that request to the edit action on the posts controller with { id: '1' } in params.
Short answer, to create a common <a> tag create a link_to, add a text to specify to where will this redirect, then the route that you've defined, you can check them by running rails routes if you're using Rails 5 or bin/rake routes if you're with Rails < 5.