You want to give each page on your sitemap its own focus keyword (or short keyword phrase). Then integrate that focus keyword into the content of that particular page. Start your keyword research by researching how your potential audience looks for you on Google.
Checkout Brian Dean’s list of SEO tools at: backlinko.com/seo-tools.
Using the KW Finder link below will open KWFinder.com in a new window to get you started. You’re limited to 2 free searches per 24 hour period however at times if the site is really busy running searches for their paying members the free option doesn’t always work.