I used to pay a subscription and could watch all the UFCs years ago, and haven’t found anything like it since it went offline. It had a nice archive of older UFC’s which made it cool too.
Try iptv
What’s a good IPTV provider?
Sounds like you’re looking for older replays which would be https://fullfightreplays.com/
Live: fbstreams.me
Newer replays: torrents
Just search UFC. Watch the day after the event. I do this a lot to avoid Rogans bullshit and just watch the fights themselves. They also have some historical but not the older stuff just the past several years.
Live stream links are ok from here but they often involve jumping around a lot due to takedowns. The bigger events are sometimes hard to get. I usually watch prelims live and the main card the following day.