The destination site sees the proxy IP, not yours. Your local network still sees you connecting to the proxy — but not the sites you open through it.
Full answer
A proxy replaces your IP with the proxy server's IP as far as the destination site is concerned. Every request that reaches the destination shows the proxy's address in the source field. This is what allows destinations to be unblocked when your country blocks them — the destination sees a request from wherever the proxy region lives, not from your country. But two important nuances: (1) Your local network (school Wi-Fi, corporate firewall, ISP) still sees you connecting to the proxy. What they cannot see is which sites you open through it — that is encrypted. (2) The destination site may still identify you via other signals — cookies from prior visits, browser fingerprint, any account you sign into. Hiding your IP is not the same as being anonymous online. For anonymity, Tor or Tor-over-VPN chains are stronger tools; a proxy is for unblocking, not for anonymity.
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