Nikola, I would guess that image sizes are having the greatest impact on page load performance.

If you were using v16 you could run optimiser for an immediate performance improvement.

Unfortunately if you stay with v14 your only option is to resample/resize and replace every image so it is optimal for the website display size.

I'm using the latest version of the program. images are minimized. I do not understand why it still has this problem.

@Nikola la segnalazione non riguarda come è fatto il sito web ma come viene gestita la cache sull'host. Se il tuo sito è su un Host Linux devi medificare  .htaccess , leggi qui:

@Nikola the report does not concern how the website is made, but how the cache is managed on the host. if your website is on Linux Host you must modify .htaccess :

https://varvy.com/pagespeed/leverage-browser-caching.html

I do not have ( .htaccess :) that at my host. I searched but I do not have it

Nikola, assuming you are hosted on a linux server, use an FTP program (eg Filezilla is free) and access your public_html folder. You will find .htaccess is a hidden file (visible in Filezilla or similar) and you can download/edit it.

(and in spite of Claudio pointing out (quite rightly) that I was wrong, if you have not run Optimiser I highly recommend it - it will NOT overwrite your existing project)

I'm telling you, it's not my web hosting that (htaccess ).I did the optimization of the site and everything is ok with me. Who on that omptimization think ....