Problem to link on frontoffice and problem connections on backoffice

[fedewebmaster]

Hello, I have a problem with my web site, that is www.fp-tech.it The problem is that the link of the product not work good with firefox and safari browser, it not work good also with Ipad. if you click on the link of a product it will not open and go on the same link where you are. It appear as if there is a cache that show Always the same page. For go on the page where I want to go I need to click after clicked the link on F5 and update the page. This problem not appear always but too much time. For see the link need to update the page from the browser. the web site work better only with Internet Explorer, but the problem is also with it.
I have also one more problem with the backorder, too much time it disconnect on every modifie and for reconnect i need to clear cookie and cronologie of the browser. If not do this it not connect.
Can you help me to solve this problem?
If you check with Google page it will appear too much error for cms and other. Can you help me to solve it? Can be this that chause the problem on navigations or can be other configurations?
 

see

https://developers.google.com/speed/pagespeed/insights/?url=www.fp-tech.it

thank you in advance.

Regards.

[fedewebmaster]

up, someone that know how to help me?