How do I install internet on my PC?

Could you kindly explain the process to me? I'm quite new to this and am a bit confused. Could you walk me through the steps of installing the internet on my personal computer? I'm not sure where to start, and I'm worried I might make a mistake. Could you please tell me what equipment or cables I might need? Also, do I need to contact my internet service provider for any assistance? It would be great if you could provide a step-by-step guide to ensure I don't miss any crucial details. Thank you so much for your help!