@Madute There are several ways.
Perhaps the most obvious is to use the Netlify Sitemaps plugin:
Discover the Top 10 Netlify Build Plugins - Discover the Top 10 Netlify Build Plugins
Another way would be to use a program such as Scrutiny to create your sitemap:
There are also online sitemap generators, such as this one:
You can even download a script to run against your site files and create one yourself: