Being famous is a short lived experience, just like clothing fashion, fame will come and go but will not necessarily make you happy or content. The real prize in life is to love and be loved for who you are as a person. Think about standing at your own funeral and what you would like your friends and family to be saying about you as a person as they describe your qualities and character as a person.
Then go and become that person!!
Also, since you are looking to get started early enough, I would recommend trying to start multiple different channels that each have a unique and different flavor/identity and see which ones pick up steam. If you have channels that are not succeeding, I would recommend deleting the ones that are dying off and starting off new experiments to take their place. It's hard to know which videos will succeed until you try. You'll want to read all of the comments and respond to comments on your videos. Anything you can do to increase engagement on your videos will be important. Plus, Youtube will be more likely to recommend your videos to other people as you increase comments on your videos. Also, finding other Youtubers who are willing to point people to your videos will be important and they will likely want you to do the same for them in return.
If you do end up getting a successful following on Youtube, you will want to find a messaging service such as Discord where you can have a group chat going on with people who have connected with your videos. The most important key to building a Youtube channel is building a community of viewers that are excited about your content. Only then will you be able to get a following of people invested enough in your videos to financially contribute, which would likely occur through Patreon.
Fame come in many facets. Fame doesn't necessarily have to come with how many people know you. Do what you stand for and make a positive impact in the world - fame will come in big and small ways.