Safety and rules
A cocked crossbow is a loaded tool with a lot of stored energy and no way to un-cock itself gently.
01 Handling
Keep fingers and thumb below the rail — the string travels along it and will take skin with it. Never dry fire. Discharge into a target rather than trying to unload a cocked bow by hand.
02 Maintenance that prevents failures
Wax the string, lubricate the rail as the manufacturer specifies, and check cables, serving and limb bolts for wear before each outing. Most catastrophic failures start as visible fraying.
03 Rules in Canada
In Canada crossbows are generally not treated as firearms, but rules on hunting with them — seasons, species, minimum draw weight — are set by each province and territory and differ substantially.
Check the current regulations for the province you will hunt in before buying, not after. This page is background, not legal advice.