WordPress inside Laravel Integration

Solution:1

To create a union user system, I suggest that you use WordPress REST API & OAuth (Authentication System) it has a WordPress plugin you can use the data for both sides, Laravel & WordPress.

To authenticate users from Laravel application to allow them to view WordPress specific directory, you should generate WordPress authentication cookies from Laravel then redirect.

I think these articles may help you to start:

How to use WordPress as a backend for a Laravel Application

Using the WordPress REST API / Authentication

WordPress REST API – OAuth 1.0a Server

Solution:2

Mahmoud, thank you.

I solved this problem with the function wp_set_auth_cookie($user_id, true);

After log-in in my system I call one function that use wp_set_auth_cookie and login the user into WordPress.