Using a sword as a self defense weapon to a burglar in your house? Is that illegal?

My brother has a sword as a decorative item. And he's wondering if he could use that sword as self defense if a burglar tries to rob his house?

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…).