Internal links are not just an SEO trick
Internal links help readers move from education to action. They also help search engines understand which pages are related and which pages are most important.
Google recommends using crawlable links and helpful anchor text in its link best practices.
Build around pillar pages
For a local business website, the pillar pages are usually service pages:
Blog posts should support those pages with related questions.
Example cluster
For booking systems:
Each article links back to the booking system service page with descriptive anchor text.
Do not overdo it
Every link should be useful. If a link would not help a reader, do not add it just for SEO.
Bottom line
Internal linking is information architecture. It turns a pile of posts into a useful library that supports your service pages and helps visitors take the next step.