VPNs give nearly no security benefit, as over 95% of websites that people actually use
already support HTTPS, which encrypts your connection. VPNs will only ever give a security benefit when you're browsing a site lacking HTTPS, which is rare.
A VPN can provide a privacy advantage since it does hide the websites you visit from people monitoring your traffic, and it hides your IP address from the websites
you visit. However, it is important to understand the limitiations of this. When using a VPN, you send all of your internet traffic to a single server, and they can
do whatever they want with it. You have to trust them fully not to do anything malicious. There is no way for you to verify that your VPN provider doesn't log. Many
VPNs have lied about their no logging polices before, such as
IPVanish. VPNs are also very vulnerable to traffic analysis attacks, in which sensitive information
can be inferred from the network traffic despite the encryption.
If you want privacy and anonymity, use Tor instead, which avoids trusting a single party and is more private by design.
Also see "Don't use VPN services" and "You want Tor Browser... not a VPN".