Thanks for reading
If you mean do you have to write all your script in JS in Unity in order for it to work on Android, the answer is no. In fact I would highly recommend that you write everything in C#.
I can see why you might ask the question, because Android is mainly Java based.
Unity takes care of creating what is needed natively on Android whether you write the Unity script using JS or C#.
There tends to be much more support for C# scripting in Unity.