HOSA questions

I recently joined HOSA at my school and registered for a competitive event: KT human growth and development
It was the last open event on there so I took it up. I’m completely clueless as to how to study for this and how the events go and all that since hosa isn’t really huge at our school

How many competitions are there per year? I seriously hope there is more than one bc I’m not particularly fascinated about human growth and development.
Which events are the best ones- I read through the guidelines and all and some of them seem interesting, I’m talking about the non-exam ones but which ones are the best ones in your opinion
How do I study for the knowledge tests- there is a list of textbooks which no I will not buy because they are overpriced and I’ll only be using them once. Is there any way I can access these textbooks without actually buying them? Theyre not at my library either
And are the events competitive-how much studying should I do for this test? I’m involved in a plethora of other activities and I still am not sure how to get the textbooks so how competitive are these KTs specifically

sorry for the overwhelmingly disastrous amount of questions
just a clueless freshman
thanks