How do I get down load code I want to download a app but it not letting me says I I need download code

Greetings Sharkbn213,

If you are attempting to download a third-party app and need a code from the developer, we’re going to recommend that you reach out to them directly. The following article shows you how to find their contact information or possibly website - How to contact an app developer

If you’re attempting to download an Apple app it would be helpful to know which app. Also, does the message that pops up specifically say a download code is required? If not, what does it say? 

Typically when downloading an app you may be asked for your Apple ID password, or maybe a two-factor verification code. If there are any profiles or restrictions set up on your device you may need a code to allow certain apps. Here’s how to check for a profile - Install or remove configuration profiles on iPhone

Install or remove configuration profiles on iPhone

Configuration profiles define settings for using iPhone with corporate or school networks or accounts. You might be asked to install a configuration profile that was sent to you in an email, or one that’s downloaded from a webpage. You’re asked for permission to install the profile and, when you open the file, information about what it contains is displayed. You can see the profiles you have installed in Settings > General > VPN & Device Management. If you delete a profile, all of the settings, apps, and data associated with the profile are also deleted.

Thanks.