Page not accessible

Hello,

In my website I’m creating it is impossible from the frontpage to access to an other page from the menu or a link. It is written:

Not Found
The requested URL /blog was not found on this server.

All the pages except the home page where I did all the section are not accessible.

How I can do it ?

Thank you !

Hi, please include your website link.

Maybe you changed Permalink Settings, go to Settings > Permalinks and Save Changes for Default.