Database logins provided below
Database user: haxuno5_PayPal
Database Name: haxuno5_PayPal
Database password: -DN,~1BQqx!9 
App Name: MyApp_Payhip_Limited
Client ID: BAACP9ACSUbocIfIxpSLwHnhZAakxLdIJvF22XccxlquH0P3Q2Pn0nf2Pa8pBrlGxXh-tO4_wa1WR3LriA
Secret: EPKyoJEz9_Irf8mE4Xaq4jCMCYN0jW4ZDjnnC7bfQ6-3Fkgtn1mv51n37h7zbEQuBdmSMKBKA8UhtwuQ

I want to create a website for invoice creation, this website will be php based and will be encrypted by password and other php methods.
These are the things I need in this website.
* Password Protection:
   * Secured with a simple password.
* Invoice Generation:
   * Sends API requests to PayPal for invoice creation.
* Direct Invoice Link:
   * Displays a link to the created invoice.
* Modern password page:
   * Enhanced UI and password saving option.
   * Fully mobile-responsive.
* Invoice creation form:
   * Added options for multiple items, discounts, taxes, customer address, and due date.
   * Allows dynamically adding items.
* Invoice management:
   * View history of previous invoices.
   * Options to edit or delete invoices.
* Mobile-friendly design:
   * Made the layout responsive for all screen sizes.
* Professional Look and Feel:
   * Redesign the page to resemble PayPal's UI for familiarity.
   * Use modern and aesthetic PayPal-like design (blue and white theme with rounded edges and shadows).
* Dynamic Item Management:
   * Add an option to remove individual items after they are added.
* Improved Layout:
   * Create a clean, segmented design.
   * Add navigation buttons at the top for "Create Invoice" and "Manage Invoices".
   * Hide the forms by default, toggled by the navigation buttons.
* Modern Buttons:
   * Use modern, responsive buttons styled similarly to PayPal's.
* Paid Invoice Sync:
   * Add a function to periodically check the PayPal API for invoice payment updates and reflect the changes in the manager.
   * Modern Design:
      * Added a navigation bar with buttons to toggle between forms.
      * Redesigned forms with proper alignment and spacing.
      * Added the ability to dynamically add/remove items.
   * Invoice Payment Sync:
      * Implement logic in the backend to periodically check the PayPal API for updates to invoice statuses.
   * Password Protection:
      * A secure login system is implemented with a "Remember Me" option.
      * Password page updated to look modern.
   * Professional Design:
      * A PayPal-like UI design.
      * Buttons styled to match PayPal’s theme (modern blue-and-white theme).
   * Dynamic Item Management:
      * You can dynamically add items and remove them with a clear remove-item button (red "×").
   * Invoice Manager Navigation:
      * Includes two sections:
         * Create Invoice (with a form).
         * Manage Invoices (for history).
   * Form Enhancements:
      * Inputs for:
         * Customer Email
         * Customer Address
         * Due Date
         * Dynamic items (name, quantity, price)
         * Discount and Tax
   * Mobile Responsive:
      * The design uses flexible layouts, making it mobile-friendly.
* I provided you the mysql database logins if needed, I have cpanel based server where curl and json and also php is enabled I want the front page to be password protected so no other person can access it. I also proivded you the client secret id and screct key so I can make invoices without visting the paypal. therefore I believe I gave you all important information you needed. I want you to provide me step by step guides after finally creating the files