A lot of activity gets tracked by your phone. Best thing is not using a smartphone, the second best thing is using a degoogled phone (like a google pixel where you replace the normal android with GrapheneOS or CalyxOS if you don't have a pixel phone).

Another thing that doesn't get a lot of attention is "fingerprinting". Basically is how "unique" you appear to the websites you are visiting. Chances are that even blocking trackers makes you "unique", so ideally you want to send false info to blend in with the other users. https://www.amiunique.org/