Given that Tarawih prayers are restricted to one Hizb due to the coronavirus pandemic, how can the Qur’an be completed in this blessed month?

Finishing the Qur'an in Tarawih prayer is desirable, not obligatory. Whoever is unable to finish the Qur'an with the Imam can pray in his home after Tarawih every night until he completes it. He may read from the Mushaf if he has not memorized it.