In an interview with Spanish sports daily AS, the 18-year-old said that he has a modest home life in Barcelona with his older sister Irene, where they share household chores such as cooking and washing dishes.
The Spain international, who has already drawn attention for his maturity on the pitch, being a key player in Barcelona's LaLiga and Copa del Rey double campaign last season, highlighted the importance of his family in keeping him in check.
"I'm just a regular guy," Cubarsi said on Thursday as he prepares with his Spain teammates for their World Cup qualifier against Georgia on Saturday. "I've got my feet on the ground. My family keeps me grounded, especially my parents and my sister."
Cubarsi, who is studying a Business Administration and Management course, said that he dedicates three afternoons a week to his coursework, ensuring he is prepared for life beyond football.
"Football doesn't leave much time, but I want to prepare myself. This course is more relaxed than university, which requires more time. That way, I can recover and study," he said.
Having grown up in La Masia, Barcelona's famed academy, Cubarsi moved in with his sister after graduating to the first team. Their parents frequently visit from their village of Estanyol in Girona.
"I'm learning to cook a few things, and if there are any dishes to wash, I wash them," he said.
Despite his grounded nature, Cubarsi is ambitious on the pitch, with a potential first World Cup appearance next year.
"I'm really looking forward to it, and I'm also excited about winning it. A World Cup is spectacular, and just being able to compete would be magnificent," he said.