My husband had been working in Calgary, Alberta ,...

We would like to inform you that if you have residence in UAE, and your husband resides in Canada with work visa, then you can ask help from a lawyer in Canada to handle filing a case against the husband to get alimony for you and your kids. Also, the lawyer can file a divorce case, note that requiring you to have the data of your husband there such as address and residence so you could file the case against him where he resides.
Moreover, you can file a case in UAE to generalize against him at the ports so when he come back, they will arrest him and force him to apply the issued judgment against him.