I’m trying to get a app downloaded for my job

You open the App Store app on the iPhone, look for the App and click on the price or "GET" buttons.

click here ➜ Download apps and games on your iPhone or iPad - Apple Support

If the App is a specific app developed by your employer, then you would need to ask your employer's IT department how to download it. They may need to issue a Profile or certificate you need to trust on your device to allow the download from a website.

Outside of that, you would need to explain where this App is located and if its meant to be run on an iPhone even?

1. Open the Settings app on your iPhone.
2. Tap General.
3. Tap Profiles & Device Management or Profiles (it depends on your iOS version).
4. Find and tap the profile that corresponds to the app you want to install.
5. Tap Trust and then confirm by tapping Trust again when prompted.