Go to a shop. Make sure you buy something with adjustable Draw Length, as it will be much more resellable if you don't like archery
The shop will measure your draw length, and fit a bow, and arrows to you. Yes the spine of the arrows must match so they fly correctly, if they don't they fishtail and lose accuracy and energy downrange.
There are some good beginner bows out there that fit adults now too and can be very adjustable in both length and weight. This is really what you should look at. Note, these bows are "average" and won't shoot as well as your "pro shop" top of the line bow that is made for either hunting specific or target specific. In general, longer bows are usually target bows, they draw smoother, and shoot a bit more forgivingly on release (less string angle and more physical weight). However they are harder to hunt with being heavier and longer.
You will need to be fit for Draw length, then you should shoot a weight that comfortable and not too hard to pull, you will shoot better that way. If you shoot the wrong draw length and arrows you will never be super successful in archery.
Everyone wants to get in on the cheap....realistically, Archery is a lot like firearms, it's not cheap to start with. If you get decent equipment that fits you and you practice, you will see some success. You don't need the newest and best.....but some old junk that doesn't fit you is not going to make you happy.
