What to roll when attacked in KULT: Divinity Lost?

I got a bit confused with the Avoid Harm and Endure Injury moves and when to trigger any of them.

While it is very clear that Engage in Combat is the right move when the PC attacks someone who is aware of the attack, what happens when the PC is attacked?

For example, during a scene, an opponent decides to reveal a knife and attack a PC. Does the player rolls for Avoid Harm or go straight to Endure Injury?

Also, several ocassions (combat or not) may require to roll for Avoid Harm, and in case of failure, the description says the PC could sustein Harm. Does that mean the player annotates the Harm directly or should she roll for Endure Injury before that?

Finaly, failing to Avoid Harm mentions that the PC suffers the full a ammount of Harm, but also the GM makes a Move. Since some of the GMs moves refer to harm/damage (Exchange Harm for Harm and Deals Damage) I want to make clear if harming the PCs is always a GM decision or an automatic effect from a failure.