do free course on udemy and youtube.
if your serious buy a good book from amazon there some really good ones that can help.
the info is around but needs to read every post.
once you understand marketing and keyword research and understand google ads setup your succeed
testing campaigns to gain best profits need to be mastered when earning.
master split testing .
a lot of ppl use a blackhat way where they buy the accounts with promotion credit on them, but they understand everything I said above.
gd luck
you can earn just as much with free traffic , paid traffic just faster but costs.