I want to develop Social Media Application for Android, which Language should i learn ?

Answer 1

For a social media app, first you need a backend. There are many technologies for backend like php, node.js, django and list goes on.
You will need a database to go with your backend, example sql, MongoDB, firebase etc.
For your android app, you have a few options. You can write native apps using kotlin or Java, or you can use one of these two popular frameworks which lets u write hybrid app for both iOS and Android-
React Native by Facebook - uses javascript to write apps
Flutter by Google - uses dart language
Along with these as you are aiming for a big project, you will need some form of version control. Git is most popular form of version control and will help u a lot maintaining your code.
All those things might seem overwhelming at first, but if anything is easy, it's not worth your time. Take small steps and start with basic stuff like weather app or notes app. Eventually you'll get there.