What a VPN does
Your device creates an encrypted connection to the VPN server. Websites generally see the VPN server's address instead of your normal public IP address.
What it does not do
A VPN does not stop websites from identifying you through accounts, cookies, browser characteristics or other information you provide.
Choosing a provider
Look for clear logging policies, transparent ownership, modern protocols, open-source clients where possible and a track record of publishing technical information.