lol, no
Advice about watching fast matches

And to play devil's advocate, getting better at chess means immersing your self in chess culture. If you're far enough along that you can watch and understand what's going on in a blitz game, then of course it's going to be valuable. The devil's in the details as usual. If you can only recognize the opening phase, does that still make it valuable? I don't know, but I do know that as you get a little better, watching high level blitz is no longer the mystery it once was. And it is kind of fun now and then, isn't it?

I actually didn't know that fast chess was so popular, then I started going on live servers to watch some match and I noticed that like 95% of them are 3 minutes long or faster. I'm too bad to really follow what's happening but I was wondering if I could learn common patterns anyway.

It's not impossible to learn something, but "is it good for improving" I have to say no :) Analyzing and studying on your own is much better. If you want to look at games, why not go to chessgames.com and replay a tournament game? Blitz chess is fundamentally different. Players will purposefully play speculative moves for the sake of the clock.

The problem is that the most popular openings, and general strategy, in blitz, is not always the same as that used in slow chess. You might be learning the wrong things. And of course bullet is another game, so not valuable at all for you at this point unless you want to be a bullet specialist (some do). My best advice is check them out now and again just for fun, but don't expect to learn anything until you're quite a bit more advanced.
Is watching high level bullet and blitz matches good for improving in standard chess?