Removing category feature from site

Hi, Can you tell me how to remove the “Category’s” completely from my site. I cannot figure out how to format the Category pages on my own so I have no choice but to remove that feature entirely because the formatting is not what I need it to be…I want it “unboxed”.

I’ve already tried several methods but it’s not letting me remove the last Category listed.

https://www.yhmcare.com/index/blog/