Yes, SEO is an additional service. It’s priced per page and has packages: Basic (free if purchasing web design), Standard or Premium.
BASIC includes - Preview on Google (input of page's title on search results and browser tabs, short description, ability to hide specific page from search results (often not used, but if you would like it can be managed), specific page URL (after your website address like: https://www.website.com/titleofyourpage ), page keywords (up to 5), delivery of preview on Google,
STANDARD - Basic + SEO up to Wix SEO Wiz standard,
PREMIUM - Basic, Standard included + Premium consultation with guidance