Please refer this article

Retrieve images using a file path stored in database in ASP.Net

In the above article FileUpload code is also written.

You just need to add 2 more FileUpload controls.

 The above article is for SQL server. You need to make use of MySQL ADO.Net objects. Like MySqlConnection and MySqlCommand etc.

Refer this article to work with MySql

Using MySQL database in ASP.Net Tutorial with example

How to use MySQL Connector in ASP.Net