Instructions to allow delegate access to your email can be found in the following Microsoft support article:
https://support.office.com/en-us/article/allow-someone-else-to-manage-your-mail-and-calendar-41c40c04-3bd1-4d22-963a-28eafec25926
Instructions to allow delegate access to your calendar can be found in the following Microsoft support article:
https://support.microsoft.com/en-us/office/share-an-outlook-calendar-with-other-people-353ed2c1-3ec5-449d-8c73-6931a0adab88