Importing old website's article into wordpress articles

Ok guys, so first lets make sure you understand me,
I am into WordPress since some time right now, I have some html,css,php knowledge. (somewhat js too but not really past the theory)
I can make some edits in code of templates + plugins.

Right now I have a client who has a very old website, html 4, made by an agency who made their own mini cms, you can only upload there not take from it, and in few days they will give me all the files.

Now this woman has more then 150 articles in her website, with URLs after the root, as follows: https://www.websitename.com/*article name*

They did not use any category whatsoever for articles.

So now, when I will build her wordpress website I need to make a redirection for each of the articles so it will be https://www.websitename.com/articles/*article name*

Now, doing all of this manually means i need to create 150 redirect rules and 150 articles, and it seems to me very not effective.

I have been told there is a thing called scraping, which means there is a way to import her entire articles into xml files, import it into articles via wordpress plugin, take from the xml file all the URLs, upload via bulk with a plugin to wordpress, and there create the redirect rules easily.

If the theory works, its cool, but I have no real knowledge about how to do so in REAL LIFE, could someone please help me to figure this out, I really want to learn these skills as they are rather important for a web developer.

Thank in advance.