The phrase "to include a keyboard" means that something comes with a keyboard as part of the package or offering.
Sentences with «to include a keyboard»
Yes, that price includes the keyboard dock as well! (theverge.com)
Please note we haven't included keyboard cases in this list. (iphonehacks.com)
For a quality tablet with included keyboard, that is not a bad price, and one that corresponds with the start of the new school year pretty well too. (tabletmonkeys.com)