hi There! i am new to the Forum I want know about On-page SEO. tell some tips and tricks of on-page

Not to dis you here but at 17 years I hope you research this before asking such a broad question. That is, you should narrow the question so it's not spam bait. Push the value of your question up.

The On page SEO is the basic strategy to any website . It includes

Robots .txt
sitemap
schema
rich snippet
header tags
meta tags etc...

For on page SEO you should consider these points:
H1 to H6 tags,
meta tags,
heading
description
website speed
website content (duplicate)
server speed

There are many things you should consider in on page seo.

The Onpage SEO is the basic strategy to any website . It includes

Robots .txt
sitemap