The short answer: An inherited apartment in Ukraine becomes fully yours once the inheritance certificate is followed by registration of your ownership in the State Register — both achievable from Canada through a representative. The main caveat: the certificate alone changes nothing in the register, and utilities, occupants, and debts tied to the property need addressing before any sale or rental is realistic.
This situation usually means the emotional part is done and the administrative part is not: a certificate in hand or in progress, an apartment with its own history — occupants, utility debts, title quirks — and a decision about its future. The work is registering cleanly and setting the property on whichever track you choose, with the paperwork done to the standard Ukrainian notaries and registries demand.