The problem of digitizing the process of handwriting in the context of electronic lessons and educational presentations?

Question

Graphics tablet

After watching this video: www.shpargalkaege.ru/b1resh/b1resh45/b1resh45.html I came to the idea of ​​creating similar presentations.
A competent combination of visual and sound methods of transmitting information in many cases can produce a tangible effect. The gradual presentation of the visual part of the material (including through handwriting), provided with appropriate oral comments, as a rule, is perceived much better than a one-time laying out of the printed text with all the comments and illustrations (and therefore very large in volume) text. If we are talking about the educational process, this statement is a generally recognized medical fact.
Actually the question is how to technically implement all this. And here a lot of sub-questions arise. First of all, I note that the Genius M610 graphic tablet used to create the video did not seem the best option to me: what we see is clearly far from free writing - the author, as it were, draws, draws every letter and number of his text. It turns out that writing together and laying out large-scale materials is out of the question at all.
Thus, the first problem that arises is the choice of a handwriting input device: a regular tablet, a graphics tablet, another touch input device, or an electronic pen (the one that writes on paper).
Next, software. What is more convenient to use when creating such presentations: Reader (in comment mode), Word, or some kind of software specially designed for such tasks?
And finally, the last one. How can this process be digitized? The only way I know of is video capture. But, perhaps, there are programs that allow you to save the entire editing procedure (as a video), and not just its result (though, in this case, in addition to everything, the question arises with attaching sound).