Pages with 2 or 3 columns

I have 2 pages:

http://www.miosoftware.it/software-gestione-orari-e-turni-di-lavoro/ it extends on 2/3 of page width (look lower part of the page);

http://www.miosoftware.it/b-point-saas-software-per-commercialisti-e-consulenti-lavoro/ it extends on the whole page;

The second solutions has been made from a programmer I don’t work anymore with.

I’m looking for some ideas how to transform the first page as the second?

Thanks and ciao