I would also like to ask another question, can the same method of restoring the site work with webmin

Elgg can't access the data directory or the cache folders within the data directory. Therefore, you get the site displayed without CSS styling etc. seemingly text only.

The question is if Elgg can't access the data directory content because the access permissions set for the files and folders on your server are not set correctly (that's what Nikolai was referring to) or if you haven't followed all instructions about how to move your site fully and correctly.

You need to update some database entries if the paths on the filesystem to the Elgg root folder and/or the data directory are different on the new server. And starting on Elgg 3 you also need to make sure that the path set in elgg-config/settings.php for data directory is correct (if different on new server you need to change).

Changes in .htaccess are only necessary if you had made any modifications on your own that contain path related data. If you not only moved the site to another server but thought to upgrade to an new major Elgg version at the same time though, this might problems not related to the server move and therefore not explained in the corresponding instructions. Never move and change Elgg version at the same time!

Any administration tools on the server won't help. It's a matter to fix within the Elgg installation (database, install and data folders).

I followed the steps in detail
Also, the site after the transfer process appears normally, but when you do the upgrade.php lines, the site turns into this shape. I also entered my account and logged in. I think this indicates that the database rules were linked correctly or what

The difference in URL is definitely not a matter related to the configuration of your VPS server.

It might be that the cache settings of Elgg ("Advanced Settings" in the admin area of your site) differ between the old site and new site and this might cause different URLs (e.g. with caching disabled or some caching options at least) the caching of the files might not be possible in the first place, so you won't get a "cache" URL.

Apart from the caching options available on the Advanded Settings you might also want to create the symbolic link in the root folder of your Elgg installation. At least for me it never worked to let Elgg create it automatically. Nonetheless, the Advanced Settings page will tell you where the "cache" link would have to point to exactly within the data directory.

Thank you iionly.

I'm going to check this.

Thank you very much Nikolai and iionly. I learn a lot from your answers.

However, I reinstalled the site from scratch and the initial tests show that it works well. The problem with the images disappeared. 

All the best.