1. I download recomended mdk from http://files.minecraftforge.net and unzip archive.
2. I open InteliJ, I Import new project and I select build.gradle from unziped archive.
3. I leave import options to default.
4. After import i wait to all files to sync then i click getIntelijRuns and prepareRunClient and after that i "Edit Configurations..." to fix runClient
4. And i run debug but errors are already there.