Soldiers who surrender are entitled to respect for their lives and integrity.

The wounded and sick must be cared for by the controlling force and the emblem of the red cross, red crescent or red crystal must be respected.

Civilians are entitled to respect for their lives, dignity, personal rights and convictions.

No punishment without trial and no one must be subjected to physical or mental torture, corporal punishment or cruel or degrading treatment.

It is prohibited to employ weapons or methods of warfare that cause unnecessary losses or excessive suffering.

Parties to a conflict must at all times distinguish between the civilian population and combatants in order to spare civilian population and property.

https://www.icrc.org/en/war-and-law/treaties-customary-law/geneva-conventions