Hi! I’m in an Ubuntu system trying to embed image or pdf’s to my notes but it doesn’t show the file nor show the preview of it. I try to drag and drop or copy paste images and it always creates a file in the vaut but doesn’t apear the image or preview.
I have no plugin installed, already tried to change attachments location and launched obsidian in restricted mode
check the actual file tree using the file manager (e.g. files/nautilus on gnome)
you can see the file there
see that the relative link follows correct path which is reflected in your link in markdown
What I do is for my note/project folder I always create a sub-foldr called img. Then I put my image myPicture01.jpg in that folder (either drag into that folder in Obsidian interface or use file manager). And then I create the link to the file in my markdown file. I prefer to just type it in source view and I would follow markdown syntax - or if you like wikilinks syntax:

# or
![[img/myPicture01.jpg]]
I use linux manjaro system btw, but I would use the same approach on Mac and Windows. You make sure the path relative to your markdown file is correct. I also use ImageCaptions plugin, which I find very helpful in displaying titles like “Title of My Picture”. If you get your images (relative paths) sorted first and then install the plugin, it gives nice instructions how to embed captions.
Same goes for any other type of files. Files will be linked and you will not start the link with the exclamation mark (that is a special case of image links in markdown). Some files, like PDFs will be displayed (browsers can render PDF, and obsidian essentially is a browser), some will be “downloaded/opened in their native app”.
P.S. With these types of applications I always see that the manual process works first, then I might develop a workflow where I rely on the mechanism of dragging files in.