You can present right from PowerPoint for the web, just open the Slide Show tab.
Before you start
Select the Rehearse with Coach and go through your presentation. You'll see on-screen guidance for pacing, inclusive language, use of filler words, and culturally insensitive phrases. Plus a dashboard at the end will summarize your talk.
If you know captions or subtitles will be needed, select Always Use Subtitles and pick the language.
When you're ready
Select Play from Beginning or Play for Current Slide if you want a different slide than the first.
With the on-screen buttons, select Previous or Next to move slides.
To view all the slides in your presentation, select See all slides. Select the slide you want to go to directly.