We recommend the following extensions/plugins for you web browser.
uBlock – remove ads and trackers automatically be sure to use the one by Raymond Hill
uBlock Matrix – control exactly what is allowed to see your web activity via explicit authorization per web site. Be sure to use the one by Raymond HillDuck
Duck Go Privacy Essentials – protect your search history online, some ad/tracker blocking
Privacy Badger – block invisible trackers
Decentraleyes – alternative Content Delivery Network to prevent common code libraries from tracking where you go online.
Using these will greatly help protect you online. Nothing is a perfect answer to all the dangers in the Internet world, but this will get you very far down the road.