So I've been looking at a new hobby for fun and to motivate me to get a bit more in shape, and for me Judo seemed to be a good choice in that it is physical, but not the point where I'd be getting / throwing punches such as in Boxing.

So I went to a lesson to try it out and had fun, but I'm not sure how learning Judo works. For an hour it was pretty much a free for all, each person would choose a partner and every 5 / 10 minutes the partner would change. Every 10 / 15 minutes the sensei would shout out to try a new technique.

Is this standard for Judo lessons? As this seems fine if you already know judo, or at least the basics, but for a beginner is this the way it is usually done? And then when it comes to each new partner I just ask them to help me out and hope for the best?

Or is there a more 'structured' way of learning Judo? Since I had the impression that, being a beginner, there'd be a way for me to learn the basics other than just hoping for the best with each partner?