How would entities be used for SEO purposes in the context of a blog for a fitness studio?

I may mess around with the google NLP APi for some of the best ranking webpages of competitors, but before I do that I wanted to ask whether it would be a good use of time.

I read and watched some content about entities and I think I understand what they are but I'm struggling to imagine how they would be used in blog posts in my niche.

I'm just trying to figure out how much time to invest in this as a non-SEO professional who knows just enough to be dangerous. My recently launched website is doing all right from a keywords perspective but if I could bring in another approach to SEO, esp one that less people are using, it might be worth my time. (My #1 focus is on GMB and local SEO.)