You did not take the SAT or ACT while in HS? Try some practice tests offered online and see if you prefer one test over the other. For your LOR, it should be a teacher who had you in class and if you were in their club that’s even better. Don’t submit a LOR from a teacher who only had you in their club unless it’s going to be able to demonstrate significant leadership on your part. You don’t want a LOR that just says you are a committed student and were of great assistance to the teacher with this club.
Your GPA is a little low and which courses you have taken resulting in the GPA will be considered such as whether they were freshman general studies or advance level courses. Something for you to consider is how hard was it for you to get that 3.7 in your courses. The rigor of an Ivy is going to be more challenging so be prepared for that.
Which ivy are you interested in applying to? When you consider the schools you want to apply to transfer to, make sure to take into account all aspects of the school, including location.
If you are planning to apply to 1 or 2 ivy schools and willing to make the time commitment, you have nothing to lose. Getting into an ivy is not going to happen for over 90% of the applicants to those schools. Give it a shot and if you are rejected keep in mind you are in good company.
Make sure to have a list of match schools as well. Good luck to you!