Arguing with your boss in private, now that's a completely different deck of Magic cards. Totally helpful, productive behaviour if done respectfully and constructively. You're there to solve problems together, having differences of opinion is natural. Thrash it out between you in a 1:1, book time to engage and brainstorm.
Be nice, be prepared, find solutions that move things forward without bruising egos, try and get them to think it was their idea.
Importantly, you're coming to a decision in which they get the final say, because it's their team. Once a decision is made, after consultation, you just gotta roll with it. Don't bitch, or moan, or rub it in if things go wrong. Chain of command. One of these days you'll be there too.
If you keep on "losing" or finding yourself in constant conflict with your boss, that suggests a deeper problem. Jobs are like relationships, they've gotta work both ways. Maybe this isn't the right one for you (or them, but just as likely you).
Anyway. Never argue with your boss _in public_. Debate in private, come to a decision and move forward.