Using Export, I created an XML file on my Desktop. I ran Importer Tool. Using that tool, I selected the XML file and uploaded it.
Up to this point, this is the right way to import content. But I never heard of saving .php file to desktop after this point. I would triple check the reason and also find out exactly what is in that .php file as its not a normal WordPress export/import process.
Anyhow, the easiest way to re-try is.
First on your NEW installation. Locate wp-content/
Usually through File Manager > public_html > wp-content
If using FTP program. then, login to your installation to locate wp-content
In there you will see wp-content/plugins and wp-content/themes etc.
Simply upload your OLD plugins in to that folder. Because export/import does NOT copy over your OLD plugins.
While there, you can also move your OLD site images which also resides in wp-content/uploads
For some reason, I was then asked to save a PHP file to Desktop, so I did it.
Something must have gone wrong, for an import shouldn’t ask you to download a file.
In any case, the native EXPERT/IMPORT features only allow you to transfer your site’s content (posts, pages, users, etc) but not plugins or even your active theme. While you can install these plugins after the import/export function, no configurations will be transferred, so you’ll have to start from scratch, which can be a pain if you’ve done some extensive customisation (eg in your theme).
A more seamless way to do your migration would be to use a plugin that can bundle everything together, and allow you to restore the complete website… either to the same domain or even to a different domain name.