Zero days are vulnerabilities in software code that someone has found but not disclosed to the maker of the software. They can then use or sell this vulnerability.
Use a different search engine than google, there are many options. Startpage is one....
Delete your Wi-Fi history as this data can allow others to get an idea of where you have been and when.
Use Graphene OS to deGoogle your phone. It is an operating system for your phone designed with privacy in mind.
Start9 Labs provide a brilliant self hosting solution. Better than keeping documents in a cloud you do not control.
Find open source tools to use instead of big tech. Much more privacy friendly and it aslo means the power can return to you, and you control your data.