1a) If you're presenting via webex/zoom never share your main screen (either share a 2nd desktop screen or single app).

1b) Try to always present without mirroring your screen. it's harder to follow with high-res, but that's an argument maybe your res is too high.

2) If using Powerpoint, use presentation mode (and preso-mode for energy settings so you don't accidentally go into lockscreen).

Barring the above, I go offline on both Outlook and Slack during presentation mode.