"We'll get married soon. I just gotta sturdy up -- I gotta propose in a fire way," he told the magazine.
Scott and Jenner started dating in April 2017 after meeting at Coachella music festival. Scott said they immediately connected and likely conceived their daughter, Stormi, in early May 2017.
"We was just two kids," the star recalled. "Maybe, like the first week, you don't know if it's real of a fling. Then the second week you're like, 'Whoa, I'm still talking to her, she's responding, I'm responding. We ain't run out of a thing to say.'"
"And it got to a point where I was like, 'I need her with me to operate. She's that one,'" he said.
The "Sicko Mode" rapper said he and Jenner bonded over movies and directors and a shared desire for normalcy.
"People don't understand how real my girl is. How ill she is," the star said.
"I like to just go outside and walk. Knowing a girl that famous, you'd think she's like, 'I need to go send somebody to do this for me' ... but we just walk out the crib," he added. "I realized what really mattered to her, which is none of this [expletive]."
Scott and Jenner welcomed Stormi in February. Scott shared a video in November of Stormi dancing to his concert in New York and discussed his daughter's birth in an interview with The Ellen DeGeneres Show the same month.
"Going into it, I was nervous and scared, because we're both young," he said. "But, you know, when you first hold a baby in your arms, it's uncontrollable ... I never thought I could just love something so hard."
Scott released his third studio album, Astroworld, in August. TMZ reported Thursday the rapper will join Maroon 5 during the band's Super Bowl half time show in February.