Why doesn't Eclipse see the Android SDK?

Question

Android

I installed Android Studio and with it the Android SDK. And since I currently do not have the opportunity to use Android Studio, I decided to work in Eclipse. I installed everything that was needed (except the Android SDK, I already had it). Eclipse runs Android SDK Manager and AVD. But when I create a project (in the eclipse-worksplace folder) I get errors in the console

C:\Users\Oleg\eclipse-workspace\MyProjectt\res\values\styles.xml:7: error: Error retrieving parent for item: No resource found that matches the given name 'Theme.AppCompat.Light'.

And a bunch of other warnings:

Answer 1

Is Eclipse still supported by someone? In terms of android? And what is the reason not to use android studio if not a secret?