I think it is as I said before: They are experts about Kodi and they think every one have the same knowledge. But we (I) don't have that. I am just an ordinary worker soon retired that try to use computer. I have a friend that use Kodi too and he understand even less than me. He always come to me and then I try to solve he´s problem too. Same you helped me this time. They should have a Kodi for Dummies!

@Captorx said:

I think it is as I said before: They are experts about Kodi and they think every one have the same knowledge. But we (I) don't have that. I am just an ordinary worker soon retired that try to use computer.

For dummies
They don't think. They are sure. :-)

NFO

It is set to check with TMDB and if that fails to check internal file information. I think they mean the NFO. Maybe that doesn't work? I can also set to check internal file information only. Not checking TMDB.

I believe that, in your case, it's better to configure it to search for information in the NFO (internal file?) and if it doesn't find it, search in TMDb.
Since you don't have movies with NFO files, this setting won't change what happens now.

Scrapers

MediaElch? Never hear that before. That is for creating scraper and work in Kodi?

There are some external to Kodi.
Ember Media Manager and tinyMediaManager are the best known.
https://forum.kodi.tv/forumdisplay.php?fid=116
And there's MediaElch that I use.
https://www.kvibes.de/mediaelch/
https://mediaelch.github.io/mediaelch-doc/index.html

If not using Synchronization with Kodi how then make Kodi to read the scrapers? Can I just put it in the Movie libarary?

Everyone scrapes and creates an NFO file with data inside the movie folder.
And download the images (Poster, Fanart and Cast).
And KODI doesn't need to scraper.
It will search the movie folder for data and images.
If KODI doesn't find an NFO in the folder, it can look it up directly in TMDb.

Since you use .RAR files in MediaElch you may need to do some configuration.
In others I don't know.

If you decide to use MediaElch, let me know here.
I can help there on his website.
If you speak German, there is a forum in German.

If I extract the rar files with the add-on for Kodi then Kodi can read the rar files like a movie file. The add-on only exract the rar files temporarly until Kodi have read them. The it work about finding the movie. But I have notice something else about the add-on. When the add-on have read the rar files it "don't let go". I mean after I have see a movie I first delete the scraper information inside Kodi and then I use to delete the movie-file itself from the hard drive. When I want to delete that I got the message that the folder can not be deleted because Kodi is using it. And that is not correct because I have stop to watch. So that time I can not delete the folder/movie from the hard drive. I must close Kodi first. That is not so good. So I think I will in the future extract the rar files with winrar before I put it in the hard drive. But I will not do that with all files I already have 1000+ and more. But with new movies. So then after maybe 2 years I do not need the rar add-on anymore. I think that is the best solution. But I am happy that we have found why new Kodi not read TMDB and that was my biggest concern. The rest is only some small issues that I can fix :-)

Yes I can speak some german but I prefer english. But I will look into that. I have saved MediaElch already and will try it. Thank you very much for your support!