Question about Samsung Galaxy Tab S3

The Galaxy Tab S3 only has a USB-C port. A USB-C to HDMI adapter doesn't work either, because Android doesn't support that. It depends on what you want to do with the projector: simply copying the display to the projector is not possible, as far as I know. For videos, the solution would be a Chromecast stick for the projector and wireless connection - but it only works with streaming or other supported apps (Youtube, Netflix, Zattoo, Google Play xxx, or some players). Or a tablet that has HDMI or MHL interface.