Xcode for OS X El Capitan

Is there a version of xcode that works with OS 10.11.6 (El Capitan)

Yes, there is. But it is too old.
According to the Xcode wiki, the latest version for OS X 10.11.6 is Xcode 8.2.1.
It was released nearly 4 years ago, in the era of Swift 3.0.

You cannot build App Store apps, you cannot run your app on recent devices through Xcode.
And Swift3 is too old to learn, the Swift language has changed drastically since then.

If you do not mind such things above, visit the More Downloads page.