I have given divorce to my husband. and I made promise on my child for not doing 2nd marriage.Is there any procedure to break this promise
In Islam, the woman doesn't have the sole right of divorce. She can 'request' a divorce, and then it's either up to the husband to declare the divorce, or a judge to make a decision. No divorce is in place on a woman's words, alone.
The second issue is that there is no (proper) swearing in Islam except by Allah. Any swear done on anything else is not really valid.
Divorce can get complicated at times, and should be asked properly from a scholar in person to discuss all that concerns your particular case. Asking it here will probably give you an idea of the solution, but you shouldn't act on an answer here.
But to answer your question, in the worst case scenario, you'll need to give the Kaffarah of breaking a promise by making a second marriage. I'm not exactly sure what the Kaffarah would be, but I think an option is to fast three days in return. Simple!