You could try to write down what you know/think about the topic beforehand to see how much you learned from the video specifically. Like I did here. It won’t be perfect since you won’t you know exactly what the video will be about. It helps when there are table of contents.
Even if you think you know nothing about a topic you can probably still guess something about it. I think being able to see how wrong you were or how different it was from your intuition can help in retaining the information.
This can possibly add a lot more effort to the project. I think it would be valuable to just quickly write down what comes to you easily about the topic, since that’s in a sense what you really know, or what you have automatized to some extent. You can also write that you don’t know the answer to this or that question.
I think it’s valuable too to rack your brain for questions you don’t know immediately. If you do arrive at conclusions by yourself through a difficult thought process I think you’ll retain and understand it better. Maybe not always worth it though.