Maybe post some pictures of the damage or try to explain what is wrong with it in more detail.
If it is just a minor break, super glue/duct tape might work, but for anything major you may need to contact your place of purchase to see if you can get a new handle or a repair job. Also, be careful when working with super glue, If you glue the wrong pieces together, it can effect the performance of your airsoft weapon.
I know that some at location retailers offer airsoft weapon repair, you can also try that.
Out of curiosity, where did you purchase your airsoft weapon?
I think the most helpful thing I can say to you is; If you do not know what you are doing when repairing your airsoft weapon, then take it to someone who does. It is better to pay someone to fix it correctly, than to be forced to buy a new one after you have broken it beyond repair.