العمليات في Microsoft 365 لإعداد تطبيقات Office، واسترداد مفاتيح المنتج، وتنشيط التراخيص.
Sorry, I saw you asked in english, so I am going to turn off the auto translation feature so I can post in english too.
You shouldn't have to keep both subscriptions. If you have the subscription via work account, you can cancel the personal subscription and just stay on the work account. Unless you want to keep your personal data in your personal account's OneDrive only, then it is best to keep both subscriptions and switch accounts accordingly.
As for duration, you need to check with the company's IT. They made the decision how long you will be assigned the license. The decision is not made by Microsoft. As for update, it will be done automatically, you don't have to manually update.