Can you bring plastic water bottle?

Yes you can

Yes you can as long as the seal is not broken. You can also bring in your own food...sub sandwich etc You are NOT allowed to bring in anything in glass or can Hope this helps you.. enjoy your time at Coors Field

Yes

You can also bring in sealed water/Gatorade. There are vendors all over right outside the gate selling water $1/Gatorade $2/ peanuts. We just bought ours from them, also went out the gate once to get more water.

I wasn't able to, but you may be lucky

You can, they just have to be empty. You can refill once inside.

I suggest a camelbak

No, You Can not