Does divorce occur through words uttered in a state of anger and by commenting on an action that occurred before the words were spoken? And is sexual intercourse between engaged couples before marriage considered zina (fornication/adultery)?

Sexual intercourse before marriage is fornication (zina). The marriage of a fornicator to the one with whom he committed fornication is not valid unless there is sincere repentance and the woman's womb is cleared by one menstrual cycle, according to the preponderant opinion. Sexual intercourse after the marriage contract and before the wedding ceremony is permissible, and the full mahr (dowry) becomes due.

Regarding the first divorce: If the husband was in a state of extreme anger and did not comprehend what he was saying, then it is considered void (laghw) and does not count. However, if he was aware of what he was saying, then it has occurred. As for the second divorce: This is a contingent divorce, and it occurs when the condition it was contingent upon is met, according to the preponderant opinion. The husband's intention behind this oath should be considered: if his intention was to make the divorce contingent upon performing this action in the future, then it does not occur if you had already done it in the past, but it will occur if you do it in the future. However, if his intention was to make the divorce contingent upon performing this action, whether in the past or the future, then the divorce occurs at that time because you had already done it in the past. Assuming the divorce has occurred, it is obligatory to inform the husband so that this divorce counts and so that he can decide on whether to reconcile with his wife.