Drew Barrymore has had many roles since her acting career began when she was a child, but she says motherhood is the "most important thing" she will ever do.

"It was positively the best moment of my life," Barrymore said, describing the moment she first saw her newborn daughter, Olive.

Barrymore, 37, gave birth to Sept. 26. She opened up about her daughter - and her marriage to art consultant Will Kopelman - to People magazine for the issue that hits newsstands Friday.

Asked about what she most was looking forward to with Olive, the "Charlie's Angels" star said: "I can't wait to pick her up from school, just being in the line of cars when she gets out. I want her to live a life where she knows we will be there. That is everything to me. That is what I wanted most when I was a kid, and it's what my kid will have."

Barrymore's tumultuous childhood is no secret. She was born into a legendary Hollywood family, and had her breakout role in "E.T. the Extra-Terrestrial" when she was 7. She wrote her autobiography when she was 14, after two stints in rehab to battle drug and alcohol addiction.

WATCH: Drew Barrymore Discusses Her Past

She and Kopelman got married in June, and she told People he is a great father and good husband.

"Will comes from a good family, he provides a strong family, it's amazing," she said. "For people who didn't have the strongest families, or traditional families, if you can create that, you have a second chance. It just makes me so emotional because it's like a miracle."

Barrymore talked about her childhood in an interview on ABC News' "Nightline" earlier this year.

"I was lost and scared," she said, describing her youth.

Raha Lewis of People magazine said Barrymore finds it important to be the best mother she can be to Olive.

"She is definitely going to be drawing on her past experiences," Lewis said. "She talked to us about wanting to provide a life to her daughter where she can show her the right boundaries and show her the right direction."

Barrymore told People that Olive will have "boundaries and consistency and protection and traditions."

"I'm trying to do things differently than I grew up. … I've got some really great blueprints of not what to do," she said.