A VPN doesn't really protect you from Google though. They get their data through trackers, which doesn't get blocked by a VPN. Obviously I'd still not use a Google VPN, because who knows what they'd do with that data
If you're hosting a VPN in your house, all traffic is going to/from your device and your home encrypted, and your home and the isp unencrypted. Since it's in your home, everything you do on the VPN tunnel can be seen on the other side by your isp.
Idk... maybe not great for privacy but I just test it (I have been a subscriber for a while and didn't know there was a VPN) and it bypasses my country blocks of certain piracy pages so so far it's kind of usefull.
Just be careful with that. If Google is logging your sessions, then your country's government can request that data. The idea that Google wouldn't keep logs is laughable.