Warning: This not might be the answer that you are thinking of but it will surely help you get an idea of how things work around here.
Background
I'm also new to Android and the mentor of my course (from which I was learning Android Development) had a habit of creating new projects in Android Studio whenever a new topic started, let it be Java Basics, Intents, Fragments or backendless. I was familiar with Git and it's working. So an idea struck in my head to create a single repository with multiple branches and keep all the projects in respective branches. Quite simple right, but things don't work in that fashion.
Research
I had looked for all the answers on whatever blogs, videos or answers on StackOverflow was present and had tried all the methods. Still, I was not able to get what exactly I wanted. In the Android Studio, when we create a new project, n number of files are created, and all of them are important.
I tried to add an existing repository into Android Studio. Firstly we cannot directly add the project into a sub-branch. Secondly, the project will not get merged, I don't know why. Link
I also tried to import the existing project into Android Studio. The projects will not contain all the files. Link
Solution
The only solution which I could find was to create a new repository every time and we can upload the changes into it. Believe me, its the best way to keep things organized.
Now there comes a problem, with so many repositories, it's hard to keep a track of all of them. So I came up with my own naming conventions for the repositories:
Android-Practice-<Project/topic name>
- just by the name we can recognize it if we need to refer anything in future and while searching for it, they will all be in a single place
Android-Project-<name>
- If we are developing our app we can use this, so all projects will be present in a single place.
PS - I like my files to be organized in a proper hierarchy order.