comments:
The best books on the three yanas I've ever seen (clear division between the three) is Chögyam Trungpa Rinpoche's The Profound Treasury of the Ocean of Dharma: https://www.amazon.com/Profound-Treasury-Ocean-Dharma/dp/B074BFD6TY Start with studying the hinayana and never forget it (CTR famously woke an entire retreat up in the middle of the night to give the one-line talk "never forget the hinayana") and practice śamatha/shiné meditation to tame your mind. The vow to take initially is the refuge vow. But it's best to have live people to talk to about your meditation practice, both initially and as you go. There are standard obstacles that talking to live humans can help you figure out easier than reading about it at home. Find a teacher with a sangha that will take you through all the ya as starting with the hinayana. This is also the start of examining teachers to see if how they teach clicks for you, gives results, and building trust both ways for later.