When managing a Facebook page, facebook business page, or fanpage facebook, it is possible to like other pages as your page.
This is actually only possible on desktop site, facebook mobile like as page is not possible on the mobile application, see below how to go to the website.
Facebook how to like as a business page
To do so, open facebook web page, logged in as a user able to manage a Facebook page.
There, click on the three dots button on the right of the recommend button, which will display the Like As Your Page option.
Facebook page options
To like the page as your own page, select which one of your pages should be the one to like, in case you administer more that one.
How to like as a page on facebook
After having selected the page, click on accept.
Like as your page on facebook
The page visited has now been liked as your own page, or in other words added to favorites of the selected page. This is how to like a page on facebook from another page, or how to like facebook pages from a business page.
How to like as your page on facebook
This is the way to show partners or other businesses that your own fb business has an interest in them.
In order to like as a facebook page on smartphone, open your browser, and not the application, and select the Request desktop site option. You can then follow above procedure.
What is a page on facebook
A facebook page is a way to promote your fb business, facebook fanpage, or any specific thing this is not yourself personally.