A page that keeps its URL needs no redirect, which covers 30 of the 45 pages in the example. When a staged replacement publishes with a changed URL, HubSpot creates a permanent redirect from the original URL, which covers the ten moving pages if they are staged as replacements. The five folded pages need redirects you add yourself.
HubSpot's URL redirects tool handles those. It creates standard redirects from one URL to another and flexible ones that follow a URL pattern, and it accepts a CSV file for bulk uploads. A new redirect is permanent (301) by default. The tool works only for domains connected to and hosted in HubSpot. If an old URL's domain is served somewhere else at launch, its redirect has to be set up there. HubSpot says a redirect can take up to 48 hours to propagate.
Google's guide to site moves with URL changes explains what to map. Each old URL should point to the page that corresponds to it. Google warns against sending many old URLs to one unrelated page such as the home page, which it may treat as a soft 404. Content merged into one page is the exception, and those old URLs can point to the combined page. Its advice on chains is to redirect straight to the final address.
The guide also asks you to update internal links, canonical tags and the sitemap to the new URLs, and to keep redirects in place, generally for at least a year. Rankings can still fluctuate while Google recrawls the site, so a correct redirect map doesn't promise unchanged traffic.