What SEO really means
SEO is the practice of making it easy for a search engine to understand your website and easy for a person to choose you once they find it. That is the whole idea. Everything else is detail.
It splits into three broad areas: the technical health of your site, the content on it, and the signals other sites send about it.
Where to start
Start with the basics that cost nothing. Make sure every page has a clear title, loads quickly on a phone, and answers one specific question.
Then claim and complete your Google Business Profile. For most local businesses this single step does more than months of blogging.
What to expect
SEO is slow and compounding. Anyone promising first-page rankings in two weeks is selling something else.