You are thinking of entering a good business which desperately needs more young people, given the seriously aging ranch/farm population.
It is a business, and too many people do not remember that, feeling that it is a way of life. Both are true, and really necessary for staying in the business long term, imo.
However, at your age, it is best you plan on getting a good education, preferably in a good Ag college. The actual day to day planning and work of raising cattle is really not the hardest part, since most of us love doing that. Much harder, and at least as important, is the book work involved in any form of farming or ranching today.
A really broad ag education is very beneficial to young people who want to own and manage cattle, or any form of farming. Knowledge of all the government rules and regulations, as well as the complex herd management decisions, financial choices, and more that is necessary to make a living in the cattle business will serve you well. That knowledge, as well as the people you will meet in school and by participating in the cattle organizations will give you a real boost up the ladder to the success required to get in and stay in the cattle business.
If you grew up in a farm/ranch family, you have a head start, but as one who had that advantage, but did not avail myself of the formal education, I sure do advise getting all the education you can. For my family, the organizations we belong to, and the contact with our state ag college have been invaluable in furthering our education, along with learning from our mistakes. We did have exceptional family leadership from our elders who were experts in understanding cattle.
An ideal situation would be if you could begin building your herd with your family helping you care for them while you go to school.
All that does not mean one cannot succeed by doing it the hard way.
mrj