Is it possible to increase the site speed if the photos are on a donor?

Question

opencart

Hello, I need some advice on this situation. Site on opencart 3
In general, there is a donor from which goods were parsed, but it was decided to make the pictures links (the developer suggested) in order not to pay a lot for hosting (20,000 goods and a bunch of photos) and the site owner supported. Yes, it's stupid, but we were offered, we agreed.
The question is how can I increase the download of pictures or a bad thing?
For reference site urban.cm

Answer 1

The most you can do is use preconnect
to ask the browser to pre-connect to the domain when you want to speed up the connection in the future.
But this won't help much, upload the pictures to yourself.