Ruby on rails, can't update database via web interface

I'm programming a Book library system with a SQL Lite database in the background. Via the console I can add and update books without a problem. And I have already made a view where I can add new books and it works great.

But now I'm trying to make a view where I can update/edit books but it doesn't work.

I'm getting an error message because its trying to call the edit method from my book_controller.rb without a book :id. Does someone have an idea why it's not calling the method with a :id?

error

Couldn't find Book without an ID 
app/controllers/book_controller.rb:30:in `edit'

routs.rb

Rails.application.routes.draw do   
  get 'users/show'   
  get 'forms/show'
  get 'tabelle/show'   
  get 'photography/show'   
  get 'computer_scientist/show'   
  get 'switzerland/show'   
  get 'book/index', as: 'book_index'   
  get 'book/show'   
  get 'book/new'   
  get 'book/create'   
  get 'book/book_prams'   
  get 'book/edit'
  get 'book/update'   
  get 'book/destroy'   
  get 'subject/show'   
  get '/book/show/:id', to: 'book#show', as: 'show_book'   
  get '/book/new', to: 'book#new', as: 'new_book'   
  get '/book/edit', to: 'book#edit', as: 'edit_book'
  delete '/book/destroy/:id', to: 'book#destroy', as: 'delete_book'   
  root 'pages#home'   
  post 'book/create', as: 'create_book'   
  put 'book/update/:id', to: 'book#update', as: 'update_book' 
end

book_controller.rb

class BookController < ApplicationController   
  def index
    @books = Book.all   
  end

  def show
    @book = Book.find(params[:id])
  end

  def new
    @book = Book.new
    @subjects = Subject.all   
  end

  def create
    @book = Book.new(book_params)
    if @book.save
      redirect_to action: "index"
    else
      @subjects = Subject.all
      render action: "new"
    end   
  end

  def book_params
    params.require(:book).permit(:title, :price, :subject_id, :description)   
  end

  def edit
    @book = Book.find(params[:id])
    @subjects = Subject.all   
  end

  def update
    @book = Book.find(params[:id])
    if @book.update_attributes(book_params)
      redirect_to action: "index"
    else
      @subjects = Subject.all
      render action: "edit"
    end   
  end

  def destroy
    Book.find(params[:id]).destroy
    redirect_to action: "index"   
  end 
end

edit.html.erb

  <main>   
    <section class="form-group">
      <%= form_with model: @book, url: update_book_path(@book.id) do |f| %>
        <p class="form-control">Title <%= f.text_field :title %></p>
        <p class="form-control">Price <%= f.text_field :price %></p>
        <p class="form-control">Subject <%= f.collection_select :subject_id, @subjects, :id, :name %></p>
        <p class="form-control">Description <%= f.text_area :description %></p>
        <p class="form-control"><%= f.submit "Buch speichern"%></p>
        <p class="form-control"><%= link_to "Abbrechen", book_index_path %></p>
      <% end %>   
    </section> 
  </main>

index.html.erb

<div class="container">   
  <% if @books.blank? %>
    <p>Es sind keine Bücher im System.</p>
  <%else %>
    <table class="table table-hover">
      <thead class="thead-light">
        <tr>
          <th>Buch</th>
          <th colspan="2">Aktion</th>
        </tr>
      </thead>
      <tbody>
        <%@books.each do |b| %>
          <tr>
            <td><%= link_to b.title, show_book_path(b.id) %></td>
            <td><%= link_to "Ändern", edit_book_path(b.id) %></td>
            <td><%= link_to "Löschen", delete_book_path(b.id), method: :delete,
             data: { confirm: "Sind Sie sicher?" } %></td>
          </tr>
        <% end %>
      </tbody>
    </table>
  <%end %>   
  <%= link_to "Neues Buch erfassen", new_book_path %> 
</div>

strong text

<main>   
  <section class="form-group">
    <%= form_with model: Book.new, url: create_book_path do |f| %>
      <p class="form-control">Title <%= f.text_field :title %></p>
      <p class="form-control">Price <%= f.text_field :price %></p>
      <p class="form-control">Subject <%= f.collection_select :subject_id, @subjects, :id, :name %></p>
      <p class="form-control">Description <%= f.text_area :description %></p>
      <p class="form-control"><%= submit_tag "Buch speichern" %></p>
      <p class="form-control"><%= link_to "Abbrechen", book_index_path %></p>
    <% end %>   
  </section> 
</main>

The problem is your routes. (And as mentioned in the other answer, the Rails conventions are not followed, be careful with singular/plural).

See how in the controller you do this in the edit method:

@book = Book.find(params[:id])

The params hash has different sources, one of them is the url. In Rails you're expected to pass the ID of the record you want to edit/update through the url. So your route should look like this:

get "books/:id/edit", to: "books#edit"

Also watch out for the update route, the one tyou have is not the standard Rails way. It should be:

patch 'books/:id/update', to: 'book#update', as: 'update_book'

Look into the resources method for routes here: https://guides.rubyonrails.org/routing.html#resource-routing-the-rails-default