Reciting Quran at Graves & Shirk of visting graves of so called Awliyas – Assim Al Hakeem

I am wondering what you have to do and say when visiting graves, I’ve been told from young that I should recite Surah fatiha, yaseen and any other surah’s that I know. But only recently have I found out that you cannot do this but I just want clarification. So what do you do when visit graves and what do you say. Also Is there hadiths to support what to say etc.