Here's the Summer '21 Release Overview Deck. 

If you haven't seen this before, it's a visual companion to the release notes and walks you through the major enhancements in Summer '21. You can slice and dice it as you wish to train yourself and your users.  This deck covers:

- Overall User Productivity

- Sales Cloud

- Service Cloud

- Tableau CRM 

- Experience Cloud

- Salesforce Mobile App

- Customization

- Developer Highlights

- Marketing Cloud

- Pardot

* Industries (FinServ, Health, etc .. )

If you'd prefer a higher level overview of the top three features across all the clouds, check out the Release in a Box deck at https://admin.salesforce.com/releaseinabox

I've shared the Powerpoint version, if you'd prefer the Google Slides version please PM me and I'll share it.