When someone types your name into a search engine, what they find depends heavily on which platforms you use. Some publish profiles to the open web, some publish a fragment, and some publish nothing at all.
Designed to be found. Pages are open, indexed and generally rank well for a name plus a discipline, because there is little competing content.
A site on your own domain is the strongest version of this, since you control the address permanently and nothing about it depends on a company's decisions.
Public profiles typically expose a name, headline, current employer and photograph to search engines, with the fuller record visible after signing in. Members can adjust how much appears publicly and can limit visibility considerably.
For many people this is the result that appears first for their name, which is why keeping it accurate matters even if you never use the platform actively.
Job seeker profiles and uploaded documents are not published to the open web. Visibility, where it exists, is to employers using the platform's own candidate search, controlled by a setting you can switch.
The public side of these platforms is listings and company pages, not people.
Content in closed workspaces is generally not accessible to search engines. Public forums are the exception, and posts there can be highly visible depending on the forum's settings and your chosen handle.
Nothing you contribute in a closed room builds a searchable professional record, which is both a privacy benefit and a real limitation if you are trying to become known.
Published posts are typically open and indexed, so a body of writing accumulates into a substantial public presence over time. Paid-subscriber content is generally an exception.
Because writing tends to be topical rather than biographical, this often surfaces for subject searches as well as for your name, which is a different kind of findability.