While there might be better, free alternatives out there, over the years I’ve drifted in and out of ForJoyTV, which is a somewhat expensive subscription service ($30/month iirc). I’ve used it to watch my favorite series live when they get new seasons, without having to wade through dodgy and (generally unreliable) livestreaming sites.
It streams Japanese TV stations live, with a 30 second ~ 2 minute delay at best, so you can tune in to watch while they’re actually airing in Japan. This includes commercials, quite a few channels to flip through, and a 7 day tv guide. You can save episodes to their app as well as go back through the channel - program list to select items up to 2 weeks old to rewatch them. (So you can, for example, go back and click on what played at 7 pm on TV Tokyo last Sunday.)
This is convenient if you enjoyed what you just watched, but don’t want to go download the episode. Wait a couple minutes after it finishes airing for it to be archived, then just click on the last 30 minute time slot to immediately begin watching again. The quality is pretty good too, ranging 720 ~ 1080p on my rural connection.