You can’t make anyone understand anything.

You can however question their belief and motivate them to consider other options.

I know you’re looking for arguments specifically for your opinion, but you should really try to avoid using arguments at all. If you set an argument, they will attack the argument and use this to dig into their existing belief on whatever is the actual topic of disagreement instead of addressing the actual topic. If you “attack” them, they will “defend”. This does not change their opinion.

It’s better to question them, so they have to think about why they believe in what they do. By questioning, you also show that you do not understand or agree with their opinion.

It also keeps the discussion about something that exists on their side. As soon as you introduce an argument, the discussion turns to being about something that you introduced, and that’s not at all what you intended to discuss or change. Be careful with that. They will attempt to make you present arguments. Don’t let them do that. It’s about what they believe.