Just seen someone get roasted for their on-page SEO, is my website that bad too?

I just read a discussion about a investing/ day trading website in which everyone said this man’s content and on-page SEO was completely awful which got me thinking.. what if everything I know is wrong? Would anyone be open to check out my websi- www. thepestdetectiveohio .com - It’s about one year old and I get almost 500 visitors a month and have a little over 450 keywords. Additionally, all content on this site is made by me and I’ve been learning in the process.

Any feedback would be great seriously! Thanks