I added the steps provided by [**docs**](https://flutter.io/setup-windows/).  

I also added Android SDK to the environmental variable but it's still remaining an issue.

I also tried [**these steps**](https://stackoverflow.com/questions/48321639/is-not-recognized-as-an-internal-or-external-command-operable-program-or-bat) but it didn't work.

[![enter image description here](https://i.stack.imgur.com/4gX2p.png)](https://i.stack.imgur.com/4gX2p.png)

Also asked on <https://github.com/flutter/flutter/issues/19805>