In my case, the information written in the modal window is not directly linked to the button. That is, the button is not some action that the user does after reading the information given in the modal. Rather, the button stands for an add on feature of the entity (modal window entity) and so it redirects the user to an entirely different page.
Yes, that's extremely common. In most cases, the modal would have the equivalent of OK and Cancel buttons (albeit with different labels) with the OK leading to a new page and the Cancel closing the modal and staying on the same page. In your case, it looks like you'd have the primary action button at the bottom leading to the new page, and the close/cancel button at the top staying on the same page.