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We recommend that you manage the add-in for your Exchange Online organization via Centralized Deployment in the Office Microsoft 365 admin center. For more information, see Manage deployment of Office Microsoft 365 add-ins in the Office365 Microsoft 365 admin center.
Before you begin, see Determine if Centralized Deployment of add-ins works for your Office Microsoft 365 organization.
Download the manifest file here.
Sign in to Office365 Microsoft 365 for business with your work account.
Select the app launcher icon in the upper-left, and choose “Admin”.
TIP: “Admin” appears only to Office365 Microsoft 365 admins.In the navigation menu, choose Settings > Services & Add-ins. If you see a message on the top of the page announcing the new Office365 admin center, click the message to go to the Admin Center Preview Integrated apps.
Scroll down in the “Integrated apps” window. There will be some add-in management options. Click in “Upload custom apps” (see About the Office365 Microsoft 365 admin center).
Choose “Deploy Add-in” at the top of the page.
Choose from one of the following options on the “Centralized Deployment” page:
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“App type” according to the add-in you want to install (either for Microsoft 365 apps or Microsoft Teams).
Then, you are able to select between uploading:
The manifest file (.xml) on this your device: For this option, select Browse “Browse” to locate the manifest file (.xml) that you want to use.
I have a A URL for the manifest file: For this option, type copy the URL in to the field provided.
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Download the manifest file here.
7. After uploading either the .xml file or the URL, you will be able to select which Users in your organization should be able to use the add-in. The option are “Just you”, “Entire organization” and “Specific users/groups”.
8. Now, in the Deployment phase, you just have to check and accept the permissions for the app to function correctly and it will be successfully deployed.