VPNs can help you protect your security on non-secure or public networks. They can help you bypass censorship and geoblocking. They hide which websites you visit from your provider. They also hide your IP from the destination site.
However, they do not automatically protect you from hacking, identity theft or data leaks. They also do not automatically make you anonymous and do not prevent social networks from collecting your data.
If you can, use the Tor network or free VPNs instead, such as RiseupVPN, which do not collect any data about you.