To get user inputs in a web app or GUI, you can use forms for structured input and flags for coded series of inputs. However, natural language input from users like SMS messages requires more advanced techniques, such as Microsoft's Language Understanding (LUIS) platform. LUIS allows you to build bots that understand the intent behind user messages and extract actionable information. By creating a LUIS app with entities and intents, you can train it on sample data and test its accuracy. In this tutorial, we built an example of how to use LUIS to process SMS messages from Vonage's API, extracting food and restaurant information and sending responses back to the sender. The demo uses ASP.NET Core and C# to integrate with the LUIS platform, and can be extended to work with other APIs and channels.