I've created a static site for a business code in plain HTML and CSS. Along the way, I've added in two WordPress installs in subdirectories, one being a blog page and another being an eCommerce site.
Now that the website has begun to grow, the client suggested making the main static site part of WordPress. Now I am most definitely not a WordPress expert and am not sure what could potentially happen so please bear with me.
I am a bit wary of installing WordPress to the root directory of the site, to replace the main site, as I fear it may break the blog and eCommerce stores since they're installed in subdirectories.
What would be the best way to go about doing this and what steps/precautions should I take.
Thanks in advance!