If-So is a server-side solution. Conditions are checked when a page with dynamic content is loaded, and content is displayed accordingly. Only one version of the content is rendered (loaded).
The content version that search engines will crawl depends on the condition you have set.
Examples:
Geolocation – If you have set a geolocation condition, the version that search engines will crawl depends on the actual location of the search bot that crawls your site.
Returning Visitor – Generally, Google and other search engines crawl the web stateless, i.e., without cookies. Search engines will crawl the version displayed for first-time visitors.
User Role/Logged-in Users – Search engines will crawl the version displayed for users who aren’t logged in.
Dynamic Link / UTM Parameters – By default, search engines treat URLs with query strings as a separate page; both the default version and the dynamic version will be crawled. In most cases, it will be wise to set a canonical so that search engines will treat the two versions as a single page.
Learn more about dynamic content and SEO