When i enter "adb install asdasd.apk" to cmd returns "error:device not found". How can I fix this?
First, familiarize yourself with a concept of AVD. That's basically an instance of the emulator - it has a bunch of settings, like the Android version to use and screen size and an SD card image.
You cannot install stuff "in the emulator" - you can only install stuff into a specific AVD. For that, you need to create and run an AVD first. For that, use "AVD Manager" from Eclipse or standalone.
Under the Android SDK folder in Explorer, run "AVD Manager". Choose an AVD (or create a new one if you don't have any). Select, click "Start".