Mainly through youtube tutorials
I hope you are only watching them for the knowledge on trading and not to choose specific coins talked about in the said videos. I say this, because majority of such YT videos are shilling projects run by users who get paid to promote their coins and sites. Do not fall for that. In a better way, learning the same things for a stock market related video will make sure you dont get manipulated into buying a shitcoin but still getting the same knowledge about trading. Something that is a suggestion from my side.
There were even some chaos created after the whole "bitconnect" thing that many many many youtubers got money from them, and they scammed people and stole money, and all those youtubers deleted their videos. Basically all of these people end up doing this because they want money, and youtubers could make a ton of money from one video.
I did marketing for many years, still doing a small amount, and I know what they are charging, even the tiniest places charge from 100 to 400 dollars, depending on if they are fake or not, fake ones charge 100 dollars and then buy views close to 10k, the real ones that are tiny charge around $400 and they have real 3-10k viewers and you can see the impact on the price when they do it.
These are the small ones, if what you watched has 100k+ views that means we are talking about close to 5k and even more, million view ones charge as much as 25k per video. So, if you are seeing a token/coin suggestion on youtube, know that it is guaranteed 100% paid, do not care how much you trust them, it is 100% guaranteed paid advertisement.