As PR, you need to be IN CANADA in order to apply to sponsor your family.
As for maintaining your PR:
As per the Immigration Act Pursuant to A28(2), a permanent resident complies with the residency obligation provisions with
respect to a five-year period if, for at least 730 days in that five-year period, the permanent resident is physically present in Canada, or:
• is outside Canada accompanying a Canadian citizen who is their spouse or common-law partner or is a child accompanying a parent;
• is outside Canada employed on a full-time basis by a Canadian business or in the public service of Canada or of a province;
• is an accompanying spouse, common-law partner or child of a permanent resident who is outside Canada and is employed on a full-time basis by a Canadian business or in the public service of Canada or of a province.