After working with older brother Elon Musk to launch tech companies Zip2 and PayPal in the 1990s, entrepreneur Kimbal Musk pivoted to an industry that would change his life: the food industry.

Today, Musk's goal is to revolutionize access to local, healthy and unprocessed food through efforts like his casual dining start-up The Kitchen and food education nonprofit organization Big Green. In a Reddit "Ask Me Anything" session on Tuesday, he brought attention to Big Green's school wellness programs and a new campaign raising money for seeds, plants and supplies for school gardens.

On Reddit, he revealed that getting involved with farming and waging war on America's food system turned out to be the perfect move. "Food is my love and when I decided to tie my passion with my purpose, my only choice was food," Musk said. "Best decision of my life."

The Kitchen, along with his other restaurants Next Door and Hedge Row, is part of Musk's mission to help improve access to fresh food across America. Earlier this year, the community-oriented, non-profit part of The Kitchen spun out into Big Green, which implements food literacy programs and provides educational outdoor gardens for school across the U.S.

While Big Green has created 378 school gardens since 2011, Musk's fundraising aims to help another 1,000 school gardens open across the U.S. by the end of 2020. Big Green's ultimate goal is to expose children to healthier habits and cut rates of chronic diseases like diabetes and obesity by providing hands-on experiences of growing fruits and vegetables.

There's a notable tie-in to his older brother's company with his fundraising campaign: In exchange for donations as little as $25, Musk is raffling off a chance to win his own fully customized Tesla —which happens to be the sixth one ever made — through the end of April.

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During the AMA, he also took the opportunity to discuss his experiences as an entrepreneur. Like many others, Musk said he is constantly learning about how best to run his business.

"My first really hard mistake was over-charging for my work when I was younger. It told me incorrectly that people did not want my product, but the truth was that I was being arrogant and pricing it out of the market," Musk said.

"I almost shut the business down. Ever since then I have been intensely focused on under-pricing until I really know the market," he added.

When it comes to handling criticism on his own entrepreneurial projects, Musk said he is his own worst enemy. "Self-doubt [is] the sh-ttiest part of being an entrepreneur. Doubt from others is usually much easier to handle," he said.

Kimbal Tesla 3 Tweet

Musk also shared advice for other entrepreneurs. "It's a great time to be an entrepreneur," he said. "[My] best advice is to just get started. Once you've started, stay true to your passion and persist through the hard times."

He added, "Building businesses is a brutal process at times but it is so rewarding building something the world values."

For those who are in their early stages of building their company and product, Musk said it's okay to "fail early and often."

"Obsess about your product. Get it out into consumers hands as fast as possible," Musk added. "Refine the product until it resonates."

Even still, as a pioneer of the farm-to-table movement in the U.S., Musk is adamant about following through with his passion for changing the way Americans of all ages eat.

"I strongly believe that success in my mission is what matters," Musk said. "Many people focus on success and happiness of themselves and I have learned that for me, a focus on the mission is what makes me happy."

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