Are the legislature, executive and judiciary part of the goverment or part of the state?

Are they government institutions or state institutions?
Surely they are state institutions because executive is basically the head of the government but the legislature and judiciary are separate (as the judiciary is supposed to regulate it). If these are all just government bodies then who regulates the government (in a cheques and balances way)? But when I read about them, it always describes them as government bodies.

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).