Mr Witehira was born in Rotorua and attended St Michael's Catholic School and Edmund Rice College, now known as John Paul College.
"I was asked to talk about my experiences and what it's like to do business in the big, wide world," Mr Witehira said. "I've been doing this for 28 years now and it's time to start giving back, if you can help, why not?"
He first worked at New World on Edmund Rd (now Four Square) and left school at 16.
"I didn't know what I was going to do - had no focus - it wasn't until somebody gave me an opportunity. I was given the chance in Kerikeri as a produce manager in New World and have worked my way up."
Wananga organiser Greg Allen of Te Arawa Tangata said the focus of the events were around rangatahi (young people) and helping them achieve their National Certificate of Educational Achievement (NCEA), the main national qualification for secondary school students in New Zealand.
"The programme has three factors, a day wananga, a marae-based homework centre and pastoral support," Mr Allen said.
"The whole idea is to expose these students to these opportunities and hear from people in key positions, Maori entrepreneurs.
"We identify those who are making a difference to speak and they really connect with our rangatahi."
John Paul College student Anaru Mokomoko said the sessions were helping improve their NCEA results.
"It's been good listening to the speakers. I'm still not sure yet what I'll do after school," the Year 11 student said.
"I'm still thinking about my options but my dream job would be something like the owner of Nike, to be able to design my own shoe."