Move WordPress keep links the same

So I have my site set up to have main index pages done in html/csss, but a sub directory that hosts my wordpress blog, so “www.domain.com” is my site, and “www.domain.com/blog” is where wordpress is.

I want to move wordpress to the main directory to replace my main index pages and have the entire site be based in wordpress from now on. But I don’t want to lose the links to my posts that exist already, as I for-see that changing the directory will throw everything off.

What is the best way to move wordpress to my main directory, but keep my existing posts with the same links? Can I just change my permalink structure to include “/blog” in front on my new posts to keep them all in the same structure?

I looked here but it doesn’t seem to answer exactly what I’m looking for:

https://codex.www.ads-software.com/Moving_WordPress

Thanks