Umineko full story doubt

I'm lazy at writting so don't mind so much

I got some doubts about umineko is witches real? is magic real? what is the real story anyway?

I read umineko and from what I understand is that after battler promise with sayo sayo reveals she is heir and family starts to kill each other and battler somehow escapes and met sayo and they both got out via boat where sayo jumps in sea, battle tries to save her but fails and becomes unconscious and meets ikou( featherine) and they start to write story on the incident Ange tries to find truth etc

So again my big question is is magic real is witches real if so what story is real anyway

Please explain with details