Keep strong! I converted in high school and was very fearful of even telling my dad that I was becoming Catholic. I am going through the rounds with my dad right now as I prepare to go to the Dominican novitiate. Partly it’s being an only child (and so no grandkids), partly its a lack of understanding since he’s an agnostic. My mom, OTOH, I have to ask to back off because she doesn’t understand discernment is a work-in-progress. Even if it is difficult to discuss with them, ultimately, your parents love you. They may fight you, but they still love you and only fight you because of that love (however misguided it may be).
First and foremost, your vocation is to holiness. That is your primary vocation and everything else should flower from that. Your secondary vocation to a state in life will come when it is needed, but it is good that you are trying to be open and listen to where God might be calling you. Right now, though, your working vocation is to be a student. Be the best student you can be–Opus Dei. Do the work of God, even if you are scrubbing a toilet. Be an evangelized evangelizer to your friends and your family, recognizing that even Jesus had a difficult time in his home town. The more you experience the Spirit working in you and through you, the better you will be able to understand what sort of charism you may be called to do.
I’m biased towards the Dominicans… but from my experience, I would highly encourage you to consider going to college first. Not just because the Dominicans require a Bachelor’s degree (many orders assist with paying college debt), but college can be an extremely important and formative time for you. If you are at a college that has a solid Catholic formation, then you can continue your discernment, transfer to a college seminary if you decide on diocesan, or enter a religious. But at least you are continuing your formation intellectually, socially, and spiritually. My personal thought is that the college years provide important social formation that can be lacking in some seminaries and formation programs. How many newbie priests do you see who seem totally awkward whenever they interact with females? Priests and Religious need to understand what it means to have an integrated sexuality, comfortable interacting with members of both sexes in a chaste and loving way as Christ did. The only way to learn that is to do it… and high school is marred with teenage drama. College is when you mature and begin to recognize a sense of authentic masculinity. Having friendships with both genders is important, especially with people that will support developing this sense of a true Christian friendship.
Check out the Newman’s Guide to Catholic Colleges or evaluate the Newman Centers and Catholic Campus Ministries at schools near you. Find out what orders are nearby. I was fortunate to find Univ of Dallas where I had a solid intellectual, social, and spiritual formation, as well as introduction to lots of different religious (Cistercians, Dominicans, Diocesan, various women religious, Opus Dei, Neo-Catechumenal Way, Fraternity of St. Peter, etc.) And although I was introduced to the Dominicans there, I didn’t find myself drawn to that province. Recognize that different provinces and different groups have different personalities in how they live out their call to evangelize. The joke is that there are only two things that God doesn’t know: how many churches there are in Rome and how many different kinds of Franciscans there are. Consider your practice (what you do) versus your mission. Franciscans are centered on a way of life (poverty, etc.), each group living the spirit of St. Francis in the way they think most fitting, and their apostolic works and mission is shaped by that. Dominicans have a mission (preaching) and their way of life is modeled to fit the mission. It’s one of the reasons why the Dominicans don’t have lots of different Dominican groups.
There are a lot of good resources out there to help you discern. The IVE Press publishes a few good booklets, one of which addresses discussing things with parents. As I am all too familiar with, there is a negative side to discussing discernment with parents or others outside of your spiritual director. Parents, family, and friends hold an impressive sway over a young man, especially one as intellectually attuned as you… and can push someone both towards or away from religious life. It is easy to begin listening to others instead of to God. Reason is a gift from God, but Satan loves to use bits of truth and reason to confuse. (A broken clock is valid twice a day!) If you do decide to discuss it with your parents (and I think you should at some point), ask them for their support and to understand that this is a process of personal understanding. It took several years to impress on my mom that she needed to back off sometimes, instead of asking me why I hadn’t applied yet. It’s not like deciding you want to be a firefighter or a doctor. Discernment continues until the day you take vows or ordination. On the other hand, she had a tendency to recognize when I was growing stale and needed a kick in the rear. Be prudent. One of the friars on PreachingFriars.org, Br. Nicholas Monco (the Harry Potter friar) has a very good story about his vocation to the OP. His parents are very Catholic, but they also had a very hard time with their only son taking a vow of poverty and not continuing the family name.
I recognize a lot of what you are going through as things I dealt with and still do! So, if you can get past my shameless plugs for Univ of Dallas and the Dominicans, I hope my ramblings have helped. Ultimately, God’s will is the only thing you need to be concerned about… everything else is in His hands.
“Be Not Afraid!” - John Paul II quoting Jesus.
“I have a mustard seed and I’m not afraid to use it!” Spiering on Benedict XVI