Young, 29, said he's currently cooking something up for Azalea's 25th birthday on June 7.
"Her birthday is coming up. I'm planning trips and everything," he told PEOPLE Saturday night at the LA Gear-sponsored Celebrity Basketball Spectacular at Equinox Sports Club in Los Angeles, a charity game to raise awareness for diabetes and obesity.
"It's going to be a big surprise," Young continued. "I can't tell you anything. You'll see next week. We're doing everything."
The couple have been together for more than a year and a half and "it's love," Young said.
So will there be a wedding in the near future?
"Of course! Of course!" he said. "But I can't give you that surprise. You're gonna ruin that surprise."
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But before popping any sort of question, Young said he had to focus on his role for evening: playing coach.
"I think it's always good to give back," he said about the game, whose participants included celebrities like The Game and Tyga (whose girlfriend Kylie Jenner came along to cheer him on).
"The tough part is trying to coach all these egos," Young said. "I don't want to get cussed out or nothing!"