Idiom for addressing the most important point
Get down to brass tacks
to start talking about the most important or basic facts of a situation:
Let's get down to brass tacks. Who's paying for all this?
Another idiom you could use is get down to the nitty-gritty.
the basic facts of a situation:
Let's get down to the nitty-gritty - how much will it cost?
[Cambridge Dictionary]