Find your App Catalog

1. Navigate to your SharePoint Admin portal. This is located at https://mytenant-admin.sharepoint.com. For example, if your company domain is https://contoso.sharepoint.com, then your admin portal is at https://contoso-admin.sharepoint.com.

2. In the navigation menu, click on More features.
3. Click on Open under Apps. This will open your App Catalog site.
4. Within this site, select Apps for SharePoint.
5. Your installed apps are listed on this page. You can upload an app by dragging it into this list, or delete an app by selecting it and clicking Files > Delete Document from the ribbon menu.