"She taught us to see people as people. All people," Spencer says

For more from Octavia Spencer, watch the full episode of The Jess Cagle Interview, streaming now on People/Entertainment Weekly Network (PEN). Go to PEOPLE.com/PEN, or download the app for Apple TV, Roku, Amazon Fire TV, Xumo, Chromecast, Xfinity, iOS and Android devices.

Although Octavia Spencer lost her mother, Dellsena, when she was just 18, the lessons left behind continue to the shape the actress.

Speaking on The Jess Cagle Interview, Spencer, 46, opened up to PEOPLE and Entertainment Weekly’s editorial director about the woman who taught her to be practical, grounded and hardworking.

The Hidden Figures star says that Dellsena, a single mom, worked as a maid and at other odd jobs to provide for her seven children. Her mother also ensured that her kids were sheltered from bigotry and boundaries.

“I had a very strong mom who made me and my sisters understand that there were no limitations on our lives except what we placed on ourselves,” Spencer says, adding: “She taught us to see people as people. All people. Taught us to understand our place in the world. And our place in the world is, if you want to be a leader, you can be that. There was no glass ceiling until I got into the real world and realized there are glass ceilings everywhere!”

Credit: Ernesto Di Stefano Photography/Getty Images

Although Dellsena never got to see her daughter become a successful actress, Spencer credits her mother with preparing her for Hollywood by teaching her that she was able to do anything.

“I think she gave me the necessary foundation to be able to do what I do,” she shares. “I think you have to have blind faith in yourself and your ability. You have to not know that there’s a wall there because if you’re constantly looking for barriers, then they will be there.”

Dellsena may have worried that her daughter wouldn’t be able to succeed as an actress, but she never doubted her, Spencer says. And her mother’s strong work ethic taught Spencer that no job was beneath her.

“You have to not see boundaries,” Spencer says. “You have to see the sky is the limit, otherwise you will never get off the ground.”