What Quran Says About Hadith [Sunni]

[FayyazValani]

Asalam Walekum Wa Rahmatullahi Wa Barkatu

The Sunni in the title is for a reason
I wanted to get my question from a sunni


i am a shia imami ismaili muslim [JAFARI , SCHOOL OF THOUGHT]

I am pretty much confused right now
have many question but will start from a smaller one

First one is regarding Sunnah
I was reading a article
http://www.quran-islam.org/main_topics/al-shahada_%28P1191%29.html
^^^ link to the article

It says that Quran is the only message nothing else should be followed

I might sound like a Quranist but
Quran Also tells that Quran is a detailed book is various places [sorry i didnt remember the ayah no reference , but i have read somewhere]

So My Question to all my brother is ,If Allah (swt) says that Quran is Complete , Detailed , Why Do People Follow Hadith , Which prophet didnt even told to collect [maybe read that somwhere too]

Then you are going to say that Quran didnt tell you about how to pray so thats why we follow hadith
But Quran Tells you That Quran Is Detailed , Complete

And 2nd part of the question is
Things Which Quran Dont Say But Hadith Say
Like About The Beard , No where is mention about the beard
About the hijab , parda , no where is mention about the parda is quran , Except , to cover chest

So What are we following those which are not mention in Quran

I dont want offend someone or to make someone angry , nor i wanted to troll someone
I am just learning about islam , and these questions arise in my mind
Please Can one who can explain in detail .
JazakAllah khair ,
Req : please dont question about anything , just give me those answer if you can , Thank you :)