Hello, Renan!
Welcome to the Android world! Congratulations on your initiative. Not what your level of knowledge to answer such a comprehensive question, so I apologize if you explain things you already know or fail to explain something you need.
To make an Android application you would use the Android Studio IDE, Java language, Object Oriented Programming (paradigm), XML language and SQLite database. If you already know the basics of these technologies, I would recommend you to follow a basic Android course on youtube, there are some very good ones, so you can better understand how each of these technologies are used within an application.
For this application you present, you would use a web service, which will be a second project in addition to the application. In that case, you would have to use a language for web systems. I recommend using Java, which also serves the web beyond Android, so that even maintain the practice of what has been used in the Android application.
The Android application will ask the data to the web service that would go up to where the event data is and collect it. Once collected, the web service returns the application data.
The application asks event data to the web service:
Application - > asks for data-> Web service - > search- > Data
After collecting data:
Web service - > send data - > application.
I hope you've been able to show how the structure would look to you in a nutshell. You will need an application and a web service, in the application you will use Android Studio, Java, Object Oriented Programming, XMl and SQLite. Here's a start video !
Hugs!