What exactly is debatable?

A. That humans have added huge amounts of CO2 to the atmosphere?

Or

B. that CO2 is a greenhouse gas?

To deny the former would be delusional. The latter has been known since the 19th century and can be easily tested empirically.

There is no debate.

I think the rate of which we are warming is debatable.

Modeling climate change is very very difficult, and we've had many wrong predictions. Which is probably why so many people are skeptical.

No, it is not debatable.

Also, no, plant food is nitrates and phosphates, CO2 is just what plants 'breath'.

Plant food, if it's anything, is sunlight.

But almost all of what you see when you look at a tree is made of water and CO2.

Water is also vital to all life. Doesn't mean you can't drown in it or that you'll want too much of it in your basement.

Plants need water, too, but that doesn’t mean they like tsunamis.

No.