How do you do keyword research, and what is search intent?

The process:

• Start from the business, not the tool. What does the site sell, and what problems does it solve? Seed terms come from products, customer language, and sales conversations.
• Expand with Keyword Planner, Search Console (which shows terms you already get impressions for — often the fastest source of opportunity), autocomplete, People Also Ask, and third-party tools.
• Analyse competitors to find terms they rank for that you do not.
• Qualify each term on search volume, difficulty relative to your site's authority, and — most importantly — commercial value.

Search intent is what the user actually wants, and matching it is more important than the keyword itself. Four types:

• Informational — "what is working capital". Wants an explanation. Serve an article.
• Navigational — "jobaaj login". Wants a specific site.
• Commercial investigation — "best accounting software". Comparing options. Serve a comparison or review.
• Transactional — "buy tally erp9". Ready to act. Serve a product or pricing page.

Note: The practical method is to search the term and look at what ranks. If the first page is all listicles, Google has decided that query wants a listicle, and a product page will not rank however well optimised. Intent mismatch is the most common reason a well-written page fails to rank, and reading the SERP is how you avoid it.