See attachment:

Exchange 2016/2019 Change Password
Instructions for Outlook Web Access
(OWA)
This document is how to change passwords for an Exchange 2019 mailbox in Outlook Web Access.
OWA Password Change Method
Step 1. Login to OWA and select the gear icon at the top right and select the Options.
Step 2. On the left under General, select My Account.
Step 3. On the bottom right, there will be a link to “Change your password“.
Step 4. Enter in your CURRENT password, then your NEW password, and repeat it to confirm and select
SAVE to make your changes.