You can, but you should be wary of the limitations and risks. A proxy can change your virtual location, which might help you access some sites, but it doesn’t offer much privacy protection. The safest and easiest way to access global services from China is with a VPN. Since proxies don’t offer strong security features, like encryption, they’re not as dependable as a VPN for protecting your personal data. This also makes it much easier for the GFW to detect and block proxy traffic — so the websites they reliably access is pretty limited.