Even if we are close to peaking emissions, we must consider the phenomenon of accumulation. Given that CO2 has an effective lifespan of around 100 years and methane about 10 years in the atmosphere, reductions in emissions now will still result in these gases accumulating and impacting the climate for decades to come.
No, even if you emit less, you are still 'accumulating', but at a slower rate. And previously released methane is still converting to co2 in the atmosphere, for decades to come.
No they won't. Only the first derivative of greenhouse gases ('emissions') will peak. Greenhouse gases itself will only peak after the world achieves net-zero.
Since you're being pedantic, greenhouse gases don't have an infinite lifetime in the atmosphere so they will start going down slightly before we hit net-zero.
I hope most understood that I meant to say peak greenhouse gas emissions.