Assume anything you post/do online/financially can and will be used to build an advertising profile on you/train AI/be shared with government authorities
Disable ad personalization/history/sharing of information via privacy settings of mobile phone, mobile apps, Google, Facebook, banks, credit cards, ISP, cellular service, everything
Turn off third-party cookies.
Use an ad-blocker on desktop and mobile. They also help prevent a lot of tracking.
Don’t use Chrome. Consider Firefox/Brave/whatever else
Avoid using ad-supported services/companies. Consider using paid alternatives. This means using alternatives to Google Search, GMail, Facebook for photos, etc etc.