BROLY is also one of my favourite anime let's forget about his villain arc, let's dive into his backstory.

Broly's father, Paragus, left Planet Vegeta due to conflict with king vegeta (VEGATA'S FATHER), Exile and a combination of personal grievances and political circumstances. 
So to protect his son, Paragus fled Planet Vegeta with Broly. 

Their departure was both a desperate measure to ensure Broly’s survival and an act of defiance against the Saiyan monarchy because King Vegeta had deemed Broly, Paragus's son, a threat due to his immense power. As a result, Broly was marked for execution by King Vegeta.

During their time in exile Paragus and Broly were stranded in space after fleeing Planet Vegeta. They eventually encountered Fritzer, a space-traveling trader and scavenger. Fritzer, who was searching for valuable resources and artifacts, discovered the two Saiyans. Seeing an opportunity, Fritzer offered them assistance, which led to a temporary alliance.

In the Dragon Ball movie "Dragon Ball Super…