Fame and fortune weren't exactly in the cards for actor and WWE superstar John Cena early on.

The 46-year-old millionaire moved from West Newbury, Massachusetts, to Los Angeles, California, in 1999, equipped with an exercise physiology degree. Finding a job in the field, however, proved harder than he'd thought, Cena told comedian Kevin Hart on Peacock talk show "Hart to Heart."

"I didn't move out to LA to pursue entertainment," he told Hart. "[I] came out here to apply my degree and really failed. ... I couldn't get any validation for that piece of paper that I paid for. That four-year certificate from Springfield College saying, 'We think you know what you're talking about.'"

After "every avenue of fitness failed," and a last-ditch effort to become a highway patrol officer fell through, Cena was met with homelessness, sleeping in the back of his 1991 Lincoln Continental and living off free pizza from a local shop.

"They had a deal where, if you could eat their whole pizza, you got it for free," Cena said, chuckling. "I used to eat there every night, a whole pizza, so I didn't have to pay, because I didn't have the money to pay the guy."

The situation was "uncomfortable," he added, but it helped him find out who he was. Cena had the option to move back home with his parents, but chose to hang on.

"I'm very fortunate for my story because it was my choice to have hard times," he said. "My father always said, 'You're my son. I love you. You're always welcome back home.' If I could get to West Newbury, Massachusetts, I would be fed. I would have a roof over my head. I would be able to regroup."

"I chose to stay out," he continued — and his perseverance paid off.

The next year, Cena enrolled in the Ultimate Pro Wrestling school, Ultimate University, and made his WWE debut shortly after, winning over 15 world championships. He remains one of the highest-paid professional wrestlers in WWE history. 

It's a job Cena didn't even know was possible.

"I did not know that wrestling was even a career option," he said. "I watched it as a young man, kind of fell out of it as an adolescent, a teenager, because it's like, 'Oh, you've gotta study hard and maybe play sports and go get a real job or whatever.'"

Cena is also well-known for his acting in films like the Fast & Furious franchise, and for his philanthropy: He earned a Guinness World Record last year for the most wishes granted through the Make-A-Wish Foundation.

Though his road was bumpy, Cena says he feels lucky, and he appreciates the journey, even the hard parts. "My whole existence is an accident," he said. "My whole existence is based on a series of fortunate events."

Disclosure: Peacock and CNBC are owned by the same parent company, NBCUniversal.

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