This is a couple of websites i have found to be useful when starting to learn about how to program in Android Studio.
Learning to build your first Android application is quite a steep learning curve as there are many concepts and new ways of thinking which you have to go through to complete your first finished project and get your App on your phone, for some testing before you think about submitting to the Google Play Store.
These are website which help guide you through the concepts and initial setup to get your first simple application built.
There is good examples which you can copy and paste to have a good starting point to then change and grow your knowledge and ability.
Tutorials Point covers a vast amount of topics on Android programming, starting with some initial concepts through to some more complicated examples.
I found Vogella to also have a lot of quality examples and a great way to understand some of the concepts by building Android apps which demonstrate specific functionality.
When working through tutorials, part of the learning experience is to ensure that your are learning about the most current technology available, for example, if you start learning about SQL Lite then maybe think about learning more about Room persistence library or maybe even looking more into using Firebase. It depends on what problem you are trying to solve, no learning is wasted but with limited time its good to investigate all the options before starting a small project.