Some are needed for the site to work at all. The rest — audience and advertising measurement — are only set if you agree. You can change your choice at any time, from the footer. Privacy policy
Strictly necessary(Always on)
Your login session, the language you picked and this very choice. Without them you cannot log in, so they cannot be turned off.
Analytics
Google Analytics: how many people visit, which pages they read, where they come from. It tells us which course draws interest, not who you are.
Marketing
Google Ads and Meta Pixel (Facebook, Instagram): show us which ad led to a signup and allow relevant ads to be shown on other sites.