You need to set up the Google Cloud Vision API token first.

The language you select here will be hardcoded, so that the person using this will always default to one language

After turning on the Cloud Vision API, paste here the API KEYS (not service accounts) to the project. Scope them to this specific API first!

If you don't want to deal with that, you can purchase access
As mentioned, this is an Open Source project that aims to help people with vision impairement. If you have ideas or requests, pull requests are open!