This video shows the steps to create a free M365 developer tenant which can be used for your own testing and learning. The tenant does not expire (so long as you've logged in every 90 days the subscription will continue to renew). The tenant provides you with 25 Microsoft 365 E5 licenses and you can pre-populate the tenant with dummy users and dummy data if you wish. How to Add Microsoft Defender for Endpoint Subscription As a note, Microsoft Defender for Endpoint isn't available with a Developer Tenant; even though it includes 25 M365 E5 licenses. There is a way around it - Go to the following URL (in a Dev Tenant browser session) to add the trial as a subscription - https://bit.ly/2YJrTou - you can then enable Defender for Endpoint Trial. This provided me with a trial that expires in 1 year. It will be interesting to see whether it renews with the default 'Microsoft 365 E5 Developer' subscription.