What are the major things need to be a focus for lead generation through the website?
The answer to this question covers a massive terrain.
You can search for generalized answers.
For more specific answers, likely best you connect with someone who is successful in your niche + talk with them about how they do lead generation.
The gold standard, write a blog about your niche + monetize with Adsense, then after you develop your own products to sell, replace the Adsense Ads with your own Ads.