Night Tripper is a starting point. A set of light and modular tools, rules and procedures. Use them as written only as long as they serve your shared goals. Hack, expand, and repurpose them without hesitation. They assume a group of three or more, with one person acting as Referee and the others as players controlling individual characters.
Night Tripper is not original. If you are familiar with the earliest 2d6 interstellar role-playing games, you’ll recognize a lineage. Night Tripper aspires to that spirit of improvisation, open-endedness and malleability.
The players create and pursue their own goals in a world sketched out by the referee. The group fills in the details of the world over time. Ideally, most of the time the referee is following the players' lead and responding to them, not the other way around.
The referee adjudicates fictional outcomes and applies rules as necessary. If something comes up and the rest of the table thinks the referee is full of it, the referee is wrong.
Roleplaying is best done with people you know, like, and trust. Talk with your group about safety and off-limits content. Research and use TTRPG safety tools.