You may have found running
composer create-project processwire/processwire is not ideal since everything goes into the
vendor folder. Instead run
composer create-project processwire/processwire . (note the full stop at the end).
However, this will only work if the directory is empty since this is how composer works. If your directory is not empty move the contents somewhere first (including all hidden files), run the command, and then move your files back.
If you get the error
[InvalidArgumentException] Project directory "/foo/bar/." is not empty then it means you left at least one file in there.