Can I buy Wi-Fi for myself?

Excuse me, I was wondering if I could purchase Wi-Fi just for myself? I'm not too familiar with the technology and wanted to clarify if there's a way to have a dedicated connection without having to rely on public networks or those provided by internet service providers. Could you possibly guide me through the process of acquiring a personal Wi-Fi setup? Perhaps there are certain devices or services that I could invest in to ensure a secure and reliable connection wherever I go. I'd greatly appreciate any information you can provide.