Welcome to 3blue1brown! The main event is, of course, the YouTube channel, which is probably the best place to explore existing videos, including the most recent uploads, ones I'd recommend, and the various series.
If you like what you see, it really is helpful for fans to subscribe. I think. Actually, I’ll level with you, I have no idea what a YouTube subscription means. If you like what you see please go give an impassioned rant to a friend about how wonderful math is.
Funding for 3blue1brown now comes primarily from community support through Patreon. This community has also been a great source of early feedback on videos before their public release, especially while working on series. There are also several perks and benefits to members, outlined on the page.
This direct-contribution model has, I believe, changed the content itself for the better. It means incentives are aligned towards putting out lessons people find most valuable, not what reaches the most eyeballs, so I am extremely grateful that this model is even possible, and for those of you who make it so.
If you want to ask questions, share interesting math, or discuss videos, take a look at the 3blue1brown subreddit. People have also shared projects they’re working on here, like their own videos, animations, and interactive lessons. When relevant, I often put these in video descriptions as added resources.