If a husband write on a simple paper that he divorces His wife three times how many times divorce has happened

ONCE, but the legality is subject to the rules and traditions of your local, regional authority. What I mean is an emotional, religious divorce may not satisfy whomever enforces your LAW. Consult not just your religious leaders, but a judge or lawyer as well for clarity.

Traditionally he must say it, So it would be up to your local religious leader on how they accept or denial. But it is to be spoken.

What's going on between the two of you that he would write such a thing in the first place? Are you in agreement with him about a divorce?

Hello Sana Afridi,

The best I can tell you to consult with your Imam, also please open the link below for more information, good luck.

https://islamqa.info/en/72291