Born on February 16, 2005, in Saint-Tropez, France, to Moroccan parents (his father is from Agadir and his mother from Marrakech), Eliesse Ben Seghir grew up in a multicultural environment. His parents moved to France in the early 2000s, and Ben Seghir developed a passion for football at a young age, playing in local clubs.

At the age of eight, Ben Seghir joined the youth academy of AS Saint-Étienne, where his talent as an attacking midfielder was quickly recognized. His technical skills, vision, and creativity on the field were honed under the guidance of experienced coaches.

In 2020, Ben Seghir moved to the youth academy of AS Monaco, where he continued his development. His performances in youth competitions have been impressive, and he is seen as a promising talent for the future of Moroccan and French football.