Don't let this word confuse you. It may end in い, but it's not an adjective, it's a noun. There are no rules in war, after all. This word describes what happens in war. Those things are battles, fights, and conflicts.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:
In a fierce battle, there's always a lot of collateral damage. One of the things that gets destroyed is your car. But you can't do anything about it, it's battle time! So you wave goodbye to your car saying, "Ta ta car (たたか)!" as you punch some jerk in the face.
Koichi looks like a battle-weary soldier today.
Whether it's quiet or noisy, I still don't like conflict.
On the way to McDonald’s he got in a bloody fight but that didn’t stop him from getting his Big Mac.