To build a proper defence against an immigration removal order, one has to understand that there are several types of removal orders and they are issued under different sections of the legal statute, the Immigration and Refugee Protection Act (IRPA). When my clients call me saying that they are about to be deported, I always ask them to show me the report of the immigration authorities as I want to know whether my client is to be deported, is ordered to depart from Canada, or has an exclusion order.
When an immigration officer receives a report under s.44 of the IRPA (meaning that it is believed that a foreign national or permanent resident is inadmissible in Canada), they may make a removal order. In some cases, there is no need to further refer the matter for an admissibility hearing to the Immigration Appeal Division (except in cases where a permanent resident is involved, with some exceptions to residency requirements).

When a foreign national is determined to be inadmissible for serious criminality, misrepresentation, or failure to obtain authorization to enter Canada, they are issued a deportation order.
In a case when a foreign national is inadmissible for failure to appear for further examination or an inadmissibility hearing, failure to establish that they hold a visa, failure to leave Canada at the end of their legal stay, or failure to comply with certain conditions, an exclusion order is issued.
The family members of the person affected by any type of removal order become subject to the same conditions.
A departure order is issued when, for example, a refugee claimant loses their case and is subject to leave Canada, or a foreigner whose permit has expired. A foreign national who receives a departure order must leave Canada within 30 days voluntarily. If they leave Canada within 30 days, they can return in the future without prior formal authorization. If, however, there is a breach in compliance with a departure order, it evolves into a deportation order.
Exclusion order: After the exclusion order is issued and the person affected leaves Canada, they can return only after obtaining prior authorization and within one year after the order was enforced. If one left Canada because of an exclusion order, they must obtain authorization to return within two years after the order was enforced.
Deportation order: To return to Canada at any time in the future, after the enforcement of the order, the person affected must obtain authorization to return.