Can you share more details about what you’ve tried and on which device+browser?
Browsers can’t display RTSP streams directly, but since you have a Blue Iris installation, you can grab the MJPEG streams and display those.
This post shows the concepts using an RTSP stream from a Wyze cam, but the concept applies to other RTSP streams + Blue Iris:
If you’re on a laptop that’s using a modern browser (like Google Chrome), you might also run into Mixed Content issues which you can workaround as noted here: