Answer by Gaurav Ramanan for How do I do a PowerPoint presentation without PowerPoint available?

Here are your options:

1. If you need the exact fidelity (animations & graphics) of your PPT but without the ability for the recipient to edit it, go for File > Export > Video (4k)
2. If you don't need animations to be preserved but everything else should be as is and the recipient shouldn't be able to edit, go for File > Export > PDF
3. If you need the recipient to edit / control the presentation with their device try the PowerPoint Web App which is free.
4. If the recipient isn't well versed with Powerpoint but they'd still like to edit the file, convert it to Google slides.