I would like to present my family with a powerpoint presentation on TV at Christmas. My problem: I have to somehow bring this presentation from my laptop to my grandparents' TV. Can I use a USB stick there and then connect it to the TV and run the presentation?
No, because a Powerpoint version would have to be installed on the TV, and this is not the case with TVs
In principle yes, provided the TV has a USB slot and knows what to do with PowerPoint data. Few TVs can do that, but you can turn the presentation into a clip
Connect laptop via HDMI?
Or use a screen mirror stick e.g. EasyCast or Chromecast (the latter only works over a Wi-Fi and must have internet at least at the beginning)
The television can't play a presentation.
At most if the picture are the pictures show. If the TV can do that.
Powerpoint presentations can also be made as a standalone version without the need for a viewer. However, very few televisions can handle it