Apply change to my game(update?)

I’ve built my first game, and after that, I’ve changed things. I added some new features and stuff.
I want to apply changes to the app that was already built. How can I do that? Or do I have to build every time I make changes?

Build the new version of your app and upload to wherever your app is available

So you mean that building my game every time there is a change is inevitable?

Yes