Save a broken limb
Broken limb from storm, how do I save the broken limb?
Certified GKH Gardening Expert
If the branch is still attached, how severe is the break? And where did the break occur, near the trunk or further out. Sometimes if branch end-weight is pruned, a cracked branch will lift up on it's own, close the wound and recover. A professional tree service has capabilities for installation of artificial support systems, cabling and bracing. But with a serious breakage and a hanging hazardous limb, it's best to remove it.
If it's a large tree and large branch breakage, I would recommend having an arborist inspect it and make a recommendation. Keep yourself safe, kids and pets out from under it until you are certain of stability and reduction of risk.