Migrating to WP

I’m migrating a website to WP and thought that “WP No Category Base” would help. The site has 100s of pages all with static page names. When I create a page in WP, it appends the menu directory structure to the page name. This ruins the site’s internal links (of which there are 1000s). Is there a way to preserve the original relative web page names without WP rendering the URLs useless?

I want all my page names to sit on the root domain, i.e., https://www.mydomain.com/page_name

I do not want them to become https://www.mydomain.com/top_level_menu/2nd_level_menu/page_name

Hope that makes sense! Thanks

https://www.ads-software.com/plugins/wp-no-category-base/