The browser identifies itself with every request, so no, you are constantly volunteering that info and that’s how you get sites your browser can render properly. You can change your browser’s “user agent” value and sites will give you different pages based on that. For apps that demand you use their app on mobile but have a web site for PCs, you can make your browser pretend to be the desktop version so you don’t have to install a spyware app, for example. Look up “user agent spoofing” if you’re curious.