Like previous seasons of Big Brother, Season 23 is a doozy in terms of the showtimes and days. Whereas other TV shows, even reality series, might air once per week, Big Brother takes up three entire days on the network.
You can watch it on CBS or Paramount Plus at 8 p.m. ET on Sundays and Wednesdays and then again at 9 p.m. ET on Thursdays for the live episode. However the live Thursday episodes do usually result in a delay in the feeds going back up afterward.
Source : https://www.distractify.com/p/how-to-watch-big-brother-live-feeds