Blender 2.6, 2.7 had a similar UI during a decade.
So, that is not surprising that there are a decade of resources about that.
2.90 was released last summer. 2.91 is last official release. It will be 2.92 in few days.
There is a new release of blender every 3 months. And currently, a part of its UI is modified every 3 months.
That design transition started with 2.80 in 2019. It was supposed to end with Blender 3.0.
But it will probably continue. 2.8 design will probably not be completed for Blender 3.0 and will require some polishing.
So, people writing tutorials and documentations, who want their production to last, are currently waiting for a stabilization of UI.
There will always be people producing with the release they have in their hands.
So, some vfx tutorials made with 2.91 are existing. But that can only be anecdotal.
You should be able to find tutorials about 2.8 fundamentals presenting basics of new UI.
But most of videos about 2.8/2.9, you can find, will probably be about demos of new features rather than in depth tutorials about a specific subject.
If you are not in a hurry, I would suggest you to download 2.91 or 2.83 LTS release and follow tutorials about 2.8 UI fundamentals and look at beginner tutorials.
If you can not wait, maybe, smarter move is to download 2.79 and follow old tutorials.
In theory, you should be able to follow old tutorials with a recent release and ask questions on support section of forum if you don’t retrieve an old button or property in new UI.
In practice, that may be fastidious to receive a reply. Needed explanations could be numerous to write and people who have knowledge to answer, may prefer spend their time doing something else.
Anyways, you can try to figure out things by your self looking at official online documentation.