Edit database.js

config/database.js

-require('dotenv').config();
-const mysql = require('mysql2');
+const { Sequelize } = require('sequelize');
 
-// สร้างการเชื่อมต่อฐานข้อมูล
-const db = mysql.createConnection({
-  host: process.env.DB_HOST,
-  user: process.env.DB_USER,
-  password: process.env.DB_PASSWORD,
-  database: process.env.DB_NAME,
-  port: process.env.DB_PORT
-});
\ No newline at end of file
+const sequelize = new Sequelize(
+  process.env.DB_NAME,
+  process.env.DB_USER,
+  process.env.DB_PASSWORD,
+  {
+    host: process.env.DB_HOST,
+    dialect: 'mysql',
+    logging: false,
+  }
+);
+
+module.exports = sequelize; 
\ No newline at end of file