Um.... um.... um.... That is like asking a doctor to explain anatomy in three easy lessons.
First, you need to do your keyword research.
Then you need to do your on-page SEO
Then you need to do your off-page SEO and keep on doing your off-page SEO until you close your web site.
You need to run analytics, measure performance, and tweak as needed.
Make website seo friendly, do proper on-page activity with good metas & alt image, always use fresh content for ur website & Seo promotion, get quality backlinks, fellow these simple step ^& be the no.1 at google search