使用提交按钮更新数据库数据

I want to update a database with new data so that when you put your text in a text-box and then click the submit button, the data will be sent to the database, with a specific id. All I want to send is brightness, with the code below. When I write something like this, and I run it, I receive a 403 error: Access forbidden. How can I fix this?I want to update a database with new data so th